Student Guide for Living Chemistry

STUDENT GUIDE FOR LIVING CHEMISTRY

DAVID A. UCKO Antioch College formerly of Hostos Community College City University of New York

BARBARA C. UCKO

ACADEMIC PRESS New York San Francisco London A Subsidiary of Harcourt Brace Jovanovich, Publishers

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Cover painting Axo- 77 by Victor Vasarely. Reproduced with permission of the artist.

INTRODUCTION

This book will help you pass your chemistry course. It serves as your private tutor, leading you along, giving you help, and asking the right questions. The Guide lets you study and review on your own, testing your understanding to help you prepare for examinations. Chemistry will come alive as you become actively involved in*mastering this subject.

Every chapter begins with a list of objectives. They state exactly what skills you should develop in a particular unit. Each objective corresponds to a section in the textbook Living Chemistry. Thus, to master objective number 2 for Chapter 1, you would study Section 1.2 in the text.

For each objective, you will find three kinds of questions to check your understanding: short answer (Study Questions), multiple-choice, and fill-in. The answers for all questions are provided at the end of the chapter. After taking the first quiz, you may find that you have answered several questions incorrectly. Yo u then know which areas need further study. For example, if you miss question 5 of a quiz in Chapter 2, you should go back to Section 2.5 in the text, studying this material again until you think that you have mastered objective 5 for this chapter.

Do not become frustrated if you make mistakes. The purpose of the quiz is to help you know what to study. When you have reviewed the material corresponding to your incorrect answers, take the next quiz in the chapter. Again, carry out the procedure described in the previous paragraph, studying those topics you have not yet mastered. The third quiz then gives you another chance to test your mastery of the chapter objectives.

Use the key word matching quiz to check your understanding of new words in the chemistry "vocabulary." First try to write down definitions of each term. Check your answers with the Glossary at the end of this guide. Then try matching each word with the correct response from the list of definitions in the quiz.

After you have completed all the quizzes in a chapter of this guide, you should be confident of your knowledge of that portion of the text. Yo u can now answer the Exercises at the end of the chapter in Living Chemistry, which may have been assigned as homework questions. Completing the quizzes in the guide has also prepared you to take the examination provided by your instructor.

ix

Matter and measurement

To demonstrate an understanding of Chapter 1, you should be able to:

1. Describe the scientific method. 2. Interpret the major prefixes of the metric system (SI). 3. Identify units of mass within the metric system. 4. Identify units of length in the metric system. 5. Identify units of volume in the metric system. 6. Find the density of a substance from its mass and volume. 7. Compare the three major temperature scales in terms of the size of

degree and the location of zero degrees. 8. Describe the properties of the three major states of matter.

STUDY QUESTIONS

1. What steps would you take in carrying out the scientific method?

1

1

2 MATTER AND MEASUREMENT

3. Write out the full word for each symbol of mass and give its size in relation to the gram (g). (a) kg

(b) mg

(c) Mg

4. Write out the full word for each symbol of length and give its size in relation to the meter, (a) cm

(b) mm

(c) km

2. Give the meaning (numerical value) of the following prefixes when added to a unit of measurement. (a) micro-

(b) milli-

ic) centi-

(d) kilo-

STUDY QUESTIONS 3

5. Write out the full word for each symbol of volume and compare their size. (a) cc

(b) cm3

(c) ml

6. If an object weighs 15 g and has a volume of 3 ml, what is its density?

7. (a) How much larger or smaller is a Fahrenheit degree (F°) than a Kelvin degree (K)? A Celsius degree (C°)?

(b) If the temperature is 0°C, what would be the reading on a Fahrenheit scale? A Kelvin scale?

8. Fill in the chart with information about the properties of solids, liquids, and gases.

Volume Shape Compressibility Density Expandibility

solid

liquid

gas


MULTIPLE-CHOICE QUIZ

1. A doctor thinks that a patient has swallowed a certain poison. Using the scientific method, the doctor tests this hypothesis by (a) consulting with other doctors (b) administering an antidote to counteract the poison (c) trying several treatments at once (d) developing a theory

2. How many millimeters are in 1 meter (m)? (a) 0.001 (b) 100 (c) 1000 (d) 0.01

3. If a patient receives 3 milligrams (mg) of a drug, the dosage is (a) 1000 times smaller than 1 g (b) 3 times larger than 1 g (c) 3000 times smaller than 1 g (d) 0.003 of 1 g

4. If a stick is 1.5 m long, it contains (a) 15 cm (b) 150 cm (c) 1500 cm (d) 0.015 cm

5. A nurse administers 0.5 liter of dextrose. This volume is the same as (a) 50 cc (b) 500 ml (c) 5000 ml (d) 0.05 cc

6. If object A weighs 10 g and has a volume of 5 ml, and object Â weighs 15 g and has a volume of 3 ml, (a) the density equals the ratio of object A to object Â (b) A is less dense than Â (c) their densities are identical (d) A is denser than Â

7. Water freezes at (a) 0°F (b) 32°C (c) 32 Ê (d) 0°C

8. If a substance is a gas, it (a) has a definite volume and shape (b) cannot be compressed (c) usually has a very high density (d) expands to fill the space it is in

FILL-IN QUIZ

1. According to the scientific method, if the results of your experiment do

not agree with your hypothesis, the must be

changed or replaced.

KEY WORD MATCHING QUIZ 5

2. If a woman buys 1 kilogram (kg) of sugar, she has bought g

of sugar.

3. Mass is measured in the metric system in terms of the

4. A person who walks a kilometer (km) walks times

farther than someone who walks 10 meters (m).

5. One liter equals cm3.

6. The density of an object is the ratio of its to its

7. There are degrees on the Celsius scale between the

temperatures of ice and boiling water.

8. A takes the shape of its container and expands only

slightly if the temperature rises.

KEY WORD MATCHING QUIZ

1. scientific method 6. temperature 2. matter 7. solid 3. mass 8. liquid 4. volume 9. gas 5. density

(a) a measure of the amount of space occupied by a substance (b) an approach in which a hypothesis is proposed to explain certain

observations and then tested by further observation and experimenta-tion

(c) the state of matter with no definite volume or shape, which expands without limit to fill the space it is in

(d) the state of matter with a definite volume and usually a rigid shape (e) the ratio of the mass of an object to its volume


(f) a measure of how "hot" or "cold" a substance is (g) the amount of matter a substance contains (h) the state of matter with a definite volume but no definite shape (i) the "stuff" all around you; anything which takes up space

ANSWERS STUDY QUESTIONS

1. First you would make observations of a particular situation or condition. Then you would propose a hypothesis to explain these observations. The hypothesis would be tested by further experimentation and observation. If your results did not agree with the original hypothesis, you would change or revise it. (If you are able to test and confirm the hypothesis many times, it becomes a theory.)

2. (a) one million times smaller, 0.000001 (b) one thousand times smaller, 0.001 (c) one hundred times smaller, 0.01 (d) one thousand times larger, 1000

3. (a) kilogram, 1000 times larger than 1 gram (b) milligram, 1000 times smaller than 1 gram (0.001 g) (c) microgram, 1,000,000 times smaller than 1 gram (0.000001 g)

4. (a) centimeter, 100 times smaller than 1 meter (0.01 m) (b) millimeter, 1000 times smaller than 1 meter (0.001 m) (c) kilometer, 1000 times larger than 1 meter

5. (a) cubic centimeter (b) cubic centimeter (c) milliliter Both the cubic centimeter and the milliliter have the same volume.

6. The density is 5 g/ml. 7. (a) f , f . Kelvin and Celsius degrees are the same size,

(b) 32°F,273 Κ

Volume Shape Compressibility Density Expandibility

solid definite usually rigid

cannot be compressed

high expand slightly when heated

liquid definite not fixed

nearly incompressible

generally lower than solids

expand slightly when heated

gas indefinite not fixed

compressible very low under normal conditions

expand without limit to occupy space they are in

T


1. (b) 5. (b) 2. (c) 6. (b) 3. (d) 7. (d) 4. (b) 8. (d)

FILL-IN QUIZ

1. hypothesis 5. 1000 2. 1000 6. mass, volume 3. gram 7. 100 4. 100 8. liquid


1. (b) 6. (f) 2. (i) 7. (d) 3. (g) 8. (h) 4. (a) 9. (c) 5. (e)

The composition of matter To demonstrate an understanding of Chapter 2, you should be able to:

1. Describe the arrangement, mass, and symbols of subatomic particles in an atom.

2. Describe the relation between protons and electrons in an atom. 3. Define the atomic number of an atom. 4. Given any two of the following—atomic number (or number of protons

or electrons), mass number, number of neutrons—find the third quan-tity.

5. Draw simple diagrams showing the nucleus and electron shells of an atom, given its atomic number and mass number.

6. Identify isotopes. 7. Identify atoms of the same element. 8. Differentiate between mass number and atomic weight. 9. Explain the arrangement of the periodic table and match the names and

symbols of the first 20 elements. 10. Given an element, state whether it is a metal or nonmetal, and give the

number of electrons in the valence shell. 11 . Identify those elements vital to health.

STUDY QUESTIONS

1. (a) Draw a diagram of an atom. Label the nucleus and give the names and symbols for the particles in the nucleus. Give the name, symbol, and location for the particle not found in the nucleus.

8

2

STUDY QUESTIONS 9

2. (a) What is the scientific basis for the popular saying, "Opposites attract?"

(b) What is the charge of a proton? An electron? A neutron?

(c) Why are all atoms neutral?

3. How do you find the atomic number of an atom?

(b) Compare the mass of the three subatomic particles.

10 THE COMPOSITION OF MATTER

4. (a) If an atom has 4 protons, 5 neutrons, and 4 electrons, what is its mass number?

(b) If an atom with 30 neutrons has a mass number of 56, what is its atomic number?

(c) What is the mass number of an atom with 12 neutrons and an atomic number of 11 ?

(d) How many neutrons are in an atom with a mass number of 9 and an atomic number of 4?

5. (a) Draw a diagram showing the nucleus and electron arrangement of an atom with a mass number of 11 and an atomic number of 5.

(b) Draw a diagram of an atom with an atomic number of 11 and a mass number of 23.

(c) Draw a diagram of lithium, which has an atomic number of 3 and a mass number of 7.

6. What are isotopes?

STUDY QUESTIONS 11

9. (a) State the periodic law.

(b) What are the horizontal rows of the periodic table called? Why do the lengths of the rows vary?

(c) What are the vertical columns of the periodic table called? Why is this name appropriate?

(d) Give symbols for these elements: helium, neon, carbon, boron, hydrogen, sodium, potassium, argon, oxygen.

(e) Name the elements represented by these symbols: Li, Be, Mg, Ca, Al, Si, P, S, CI, F. N.

7. (a) What must all atoms of a particular element have in common?

(b) How can the atoms that make up an element differ?

8. When dealing with elements, why must you use atomic weights rather than mass numbers?


10. (a) Why are the chemical properties of the members of a group so similar?

(b) For the following elements write Ì for metal and Í for nonmetal and give the number of electrons in the valence shell: selenium, potassium, barium, krypton, chlorine.

11 . List ten elements important to health and their symbols.


1. Most of the atom consists of (a) the nucleus (b) neutrons (c) empty space (d) protons

2. All atoms are neutral because (a) all atoms contain neutrons (b) the charge of the protons balances the charge of the electrons (c) the charge of the protons cancels the charge of the neutrons (d) the total of protons and neutrons equals the number of electrons

3. If an atom has 17 protons, 18 neutrons, and 17 electrons, its atomic number is (a) 17 (b) 18 (c) 34 (d) 35

4. An atom with 4 protons, 5 neutrons, and 4 electrons (a) has a mass number of 13 (b) has an atomic number of 9

MULTIPLE-CHOICE QUIZ 13

(c) has a mass number of 4 (d) has an atomic number of 4

5. Which statement is false about the atom shown below?

(a) The mass number is 12. (b) The atomic number is 6. (c) The outer shell can hold no more electrons. (d) The protons plus neutrons equal the mass number.

6. The identity of an atom is determined by (a) its atomic number (b) its mass number (c) the number of neutrons it contains (d) whether or not it has isotopes

7. Elements are made up of atoms possessing (a) identical mass numbers (b) identical atomic numbers (c) different atomic numbers (d) the same number of neutrons

8. Because most atoms have isotopes, most elements have atomic weights that (a) are expressed by simple whole numbers (b) are identical to the mass number (c) cannot be expressed by simple whole numbers (d) are identical to the atomic number

9. Each horizontal row of the periodic table (a) contains elements with similar chemical properties (b) represents the filling of one shell of electrons (c) presents the elements in order of decreasing atomic number (d) contains elements with the same atomic weight

10. The most metallic elements are found (a) at the lower left-hand side of the periodic table (b) at the lower right-hand side of the periodic table (c) at the upper left-hand side of the periodic table (d) at the upper right-hand side of the periodic table

11 . Which statement about carbon is false! (a) All plant and animal life is based on carbon. (b) Carbon can be found in many forms.


8. To find the atomic weight of an element, you must find the average of

the of its isotopes as found in nature.

9. In the periodic table, the elements are arranged in the order of increas-

ing .

10. The outermost energy level of an atom is called its

(c) Carbon is an active metal. (d) Diamonds are made of carbon.

FILL-IN QUIZ

1. The energy level closest to the nucleus (K shell) holds up to

electrons; the next level (L shell) holds up to electrons.

2. In all atoms, the number of is always the same as

the number of ,

3. The smallest known atom has an atomic number of .

4. Because their mass is so small, are ignored when deter-

mining the mass number of an atom.

5. If its first and second shells (K, L) are completely filled, the atom

contains electrons.

6. Hydrogen (atomic number 1, mass number 1) and deuterium (atomic

number 1, mass number 2) are examples of .

7. A large collection of atoms with the same atomic number is called a(n)


11 . The only element that can be used by the body in its elemental form is


1. atom 9. mass number 2. proton 10. isotope 3. neutron .11 . element 4. electron 12. atomic weight 5. nucleus 13. periodic law 6. energy level (shell) 14. metal 7. atomic number 15. nonmetal 8. atomic mass unit 16. valence shell

(a) the central core of an atom, which contains protons and neutrons (b) a positively charged subatomic particle found in the nucleus of an atom (c) a negatively charged subatomic particle found in shells that surround a

nucleus (d) the basic building block of nature (e) a number equal to the number of protons in the nucleus of an atom;

the most important identification of an atom (0 a large collection of atoms which have the same atomic number (g) a unit of mass based on carbon in which one proton, or one neutron,

has the value of 1 amu (h) the properties of the elements repeat in a regular way when the

elements are arranged by their atomic number (i) the total of protons and neutrons in the nucleus of an atom (j) a subatomic particle with no charge, found in the nucleus of an atom (k) a definite region surrounding the nucleus where electrons are most

likely to be found (1) an atom related to another atom by having the same atomic number,

but which has a different mass number (m) the average of the atomic masses of the isotopes of an element as they

are found in nature (n) the outermost energy level of an atom (o) the category into which only 17 elements fall; a substance which is dull

in appearance and which conducts heat and electricity poorly (p) the category into which most elements fall; a substance which is shiny

in appearance and which conducts heat and electricity well



(a)

È _ nucleus — protons (p) neutrons (n)

electron shell (energy level)

electron (e)

2.

3.

4.

5.

6.

7.

(b) The masses of protons and neutrons are about the same. The electron has a much smaller mass, 1/1836 the mass of protons and neutrons, or almost 2000 times smaller.

(a) Opposite charges (positive and negative) pull themselves together, or are attracted to each other. In addition, like charges (both negative or both positive) push each other apart, or repel each other.

(b) Protons have a positive charge. Electrons have a negative charge. Neutrons have no charge—they are neutral.

(c) Atoms are neutral because the number of protons is the same as the number of electrons—the positive and negative charges balance each other.

Find the number of protons in the nucleus of an atom, or the number of electrons. This number corresponds to the atomic number for the atom. (a) 9 (4 + 5 = 9) (b) 26 ( 5 6 - 3 0 = 26) (c) 23 (12 + 11 = 23) (d) 5 ( 9 - 4 = 5)

Isotopes are forms of an atom which have the same number of protons (and electrons) but different numbers of neutrons, thus different mass numbers. (a) They must have the same atomic number, that is the same number of protons

(and electrons). (b) They may have different mass numbers because they may have different

numbers of neutrons. Atomic weights take into account the various isotopes that make up an element. The atomic weight of an element is the average of the atomic masses of its isotopes as they are found in nature.

8.

ANSWERS 17

9. (a) The properties of the elements repeat in a regular (or periodic) way when arranged by their atomic numbers.

(b) periods; because each row represents the filling of one shell of electrons (c) groups (or families); the elements in each group possess similar chemical

properties. (d) He, Ne, C, Β, H, Na, K, Ar, Ο (e) lithium, beryllium, magnesium, calcium, aluminum, silicon, phosphorus, sul-

fur, chlorine, fluorine, nitrogen 10. (a) The chemical properties are similar because each element in the group has the

same number of valence electrons, (b) selenium: N, 6; potassium: Μ, 1; barium: M, 2; krypton: N, 8; chlorine: N, 7

11. hydrogen, H; oxygen, O; carbon, C; nitrogen, N; calcium, Ca; phosphorus, P; potassium, K; sulfur, S; chlorine, CI; sodium, Na


1. (c) 7. (b) 2. (b) 8. (c) 3. (a) 9. (b) 4. (d) 10. (a) 5. (c) 11. (c) 6. (a)

FILL-IN QUIZ

1. 2,8 2. protons, electrons 3. one 4. electrons 5. 10 6. isotopes

7. element 8. mass numbers 9. atomic numbers

10. valence shell 11. oxygen


1. (d) 9. (i) 2. (b) 10. (1) 3. 0) 11. ( 0 4. (c) 12. (m) 5. (a) 13. (h) 6. (k) 14. (P) 7. (e) 15. (o) 8. (g) 16. (n)

Chemical bonding


1. Relate the octet rule to chemical bonding. 2. Describe the formation of a covalent bond. 3. Relate the terms atom, molecule, formula. 4. Draw Lewis symbols for atoms. 5. Identify the diatomic elements. 6. Determine whether a bond is polar or nonpolar. 7. Draw Lewis structures for simple covalent molecules. 8. Match the names and formulas of (binary) covalent compounds. 9. Describe the formation of cations and of anions.

10. Given an element, write the symbol for the ion it forms. 11 . Compare ionic compounds to covalent compounds. 12. Write the formula of ionic compounds, given the metal and nonmetal

involved or the ions present. 13. Write the names and symbols for the common polyatomic ions.

STUDY QUESTIONS

1. (a) How does an atom get a complete valence shell?

18

3

STUDY QUESTIONS 19

2. How is a covalent bond formed?

3. What does " 2 0" represent?

What does " 0 2 " represent?

4. Give Lewis symbols for the following atoms: (a) helium (f) oxygen

(b) lithium (g) fluorine

(c) boron (h) neon

(d) carbon (i) hydrogen

(e) nitrogen (j) beryllium

(b) State the octet rule and explain how it got its name.

20 CHEMICAL BONDING

6. (a) Identify the following as polar covalent or nonpolar covalent molecules: HC1, 0 2 , N 2, CO.

(b) What is the difference between a polar and a nonpolar covalent bond?

7. Draw Lewis structures for the following simple covalent molecules: S i F4, P C l3, H2S, I 2.

8. (a) Give the names for these compounds: P F5, CO, S 03.

(b) Give the formulas for these compounds: nitrogen dioxide, carbon tetrachloride, dinitrogen pentoxide.

5. (a) What is a diatomic molecule?

(b) List the diatomic elements.

STUDY QUESTIONS 21

(b) How are ions formed?

(c) What is the difference between a cation and an anion?

10. Give the name and symbol of the ion formed by each element below: sodium, calcium, aluminum, chlorine, oxygen, sulfur, nitrogen, iron (give both forms).

11 . (a) How do ionic compounds differ from covalent compounds?

9. (a) How do ions differ from neutral atoms?

22 CHEMICAL BONDING

(b) What is the smallest part of an ionic compound? A covalent compound?

12. Write the formulas and names for the compounds formed by the following combinations of elements: potassium and iodine, zinc and oxygen, aluminum and bromine, calcium and nitrogen.

13. (a) List two polyatomic ions that contain hydrogen and oxygen (give names and symbols).

(b) List two polyatomic ions that contain hydrogen, carbon, and oxygen (give names and symbols).

(c) What is the name and formula of the polyatomic ion that contains phosphorus and oxygen?


1. A chemical compound is made up of (a) a mixture of atoms (b) noble gases bonded together (c) atoms with complete valence shells which are then bonded to

become incomplete (d) two or more atoms joined through bonding

2. When two hydrogen atoms are brought together, (a) the electrons, which are negative, attract each other (b) the positive electron of each atom repels the other atom


(c) the negative electron of each atom is attracted by the positive nucleus of the other atom

(d) the negative electron of each atom is attracted by the neutral nucleus of the other atom

3. If three oxygen atoms are chemically bonded together, the correct formula is (a) 30 (b) 0 3 (c) 1 0 2 (d) 0 2 + Ï

4. Only electrons are shown in a Lewis symbol. (a) valence (b) eight (c) bonded (d) two

5. In order for oxygen to have a filled valence shell, it must (a) gain an electron (b) form a double bond with a second oxygen atom (c) lose two electrons (d) share one electron with another oxygen atom

6. In HQ, the chlorine attracts the electrons more than the hydrogen does largely because (a) chlorine has more electrons than hydrogen (b) chlorine has more protons in its nucleus than hydrogen does (c) chlorine has more neutrons in its nucleus than hydrogen does (d) HC1 is a polar covalent molecule

7. Nitrogen, which has a valence of 3, can form (a) single bonds with three hydrogen atoms (b) double bonds with two oxygen atoms (c) double bonds with three hydrogen atoms (d) single bonds with two oxygen atoms

8. Select the correct sequence of prefixes to indicate 2, 3, 4, 5, and 6 atoms, respectively. (a) di, tri, tetra, hexa, penta (b) di, tri, hexa, tetra, penta (c) di, tri, tetra, penta, hexa (d) di, tri, penta, tetra, hexa

9. Ions are formed when (a) one or more electrons are shared (b) at least two nonpolar bonds are created (c) electrons are transferred from one atom to another (d) neutral atoms are created

10. When an atom loses one or more electrons during oxidation (a) a cation is formed (b) an anion is formed (c) the atom always becomes neutral (d) the atom undergoes reduction

24 CHEMICAL BONDING

11 . An ionic bond (a) forms when two atoms gain or lose a pair of electrons (b) results from oxidation (c) forms when two nonmetals chemically combine (d) results from the attraction between cations and anions

12. When magnesium and chlorine react, they form (a) Mg2Cl (b) Mg3Cl 2 (c) Mg2Cl 3 (d) MgCl2

13. The correct formula for sulfate ion is (a) S 03

2" (b) S 04

2~ (c) S 03

3~ (d) S 04

3"

FILL-IN QUIZ

1. All matter consists of either or

2. A bond is formed when the nuclei of two atoms

share a pair of electrons.

3. The smallest part of a compound which still has the properties of that

compound is a ,

4. The number of dots in the Lewis symbol is often the same as the

of the atom in the periodic table.

5. The simplest covalent molecule possible, which consists of two atoms

bonded together, is called ,

6. is the attraction of an atom for the

electrons in a chemical bond.

7. Carbon has a or "combining capacity" of 4,

since it must form four bonds for a complete outer shell.

8. According to the formal rules for naming compounds, water ( H20)

would be called ,


9. A positively charged ion is a ; a negatively

charged ion is a .

10. When an atom gains electrons, a process called ,

an anion forms.

11 . A bond is formed when sodium combines with

chlorine.

12. In ionic bonding between two atoms, the number of electrons

by one atom is the same as the number of

electrons by the other atom.

13. A group of atoms with a positive or negative charge is called a


1. compound 9. ion . 2. covalent bond 10. cation - 3. molecule 11 . anion - 4. formula 12. oxidation - 5. nonpolar 13. reduction . 6. polar 14. ionic bond - 7. electronegativity 15. formula unit - 8. valence

(a) a positively charged ion (b) the gaining of one or more electrons (c) a negatively charged ion (d) an electrically charged atom which has either gained or lost one or more

electrons (e) the smallest part of an ionic compound which still has the properties of

that compound (f) a bond formed by the attraction between oppositely charged ions (g) the loss of one or more electrons

26 CHEMICAL BONDING

(h) the "combining capacity" of an atom; the number of single bonds an atom can form

(i) a bond formed by the sharing of a pair of electrons between the nuclei of two atoms

(j) a substance which consists of units formed by two or more atoms joined through bonding

(k) a "shorthand" way of expressing the numbers and kinds of atoms in a molecule

(1) the unit formed by the covalent bonding of two or more atoms (m) unequal sharing of electrons (n) equal sharing of electrons (o) the attraction of an atom for the electrons in a chemical bond


1. (a) An atom gets a complete valence shell by joining with another atom to share, gain, or lose electrons,

(b) Atoms combine to permit each to have the electron arrangement of a noble gas, a filled valence shell of (usually) eight electrons. Octet ("8") refers to the number of electrons in the complete valence shells of most lighter elements.

2. A covalent bond is formed by atoms combining their valence shells and sharing one or more pairs of electrons between them.

3. Two separate atoms of oxygen; an oxygen molecule made up of two oxygen atoms chemically bonded together.

4. (a) He: (b) L i - (c) Β · (d) · C: (e) ·Ν:

(f) · ä : (g) F: (h) :Ne : (i) H- (j) Be :

5. (a) A diatomic molecule is a molecule consisting of two atoms of the same element bonded together,

(b) hydrogen, fluorine, chlorine, bromine, iodine, oxygen, nitrogen 6. (a) polar covalent, nonpolar covalent, nonpolar covalent, polar covalent

(b) A nonpolar covalent bond results when electrons are shared equally between two identical atoms. A polar covalent bond results when electrons are shared unequally between two different atoms. One part, or pole, of the molecule becomes somewhat positive; the other part, or pole, becomes somewhat negative.

7. X X X X F X

X

• · X · X X X X X X

F χ Si X F £ X Ρ X CI ·· • X X X X X • X X X

X X F

X X

X X

X X CI

X X

X X

• · · · X X

Η x S x Η : é χ ΐ χ xx

ANSWERS 27

8. (a) phosphorus pentafluoride, carbon monoxide, sulfur trioxide (b) N 0 2, C C 1 4, N 20 S

9. (a) Ions do not have the same number of protons as electrons and thus are electrically charged atoms. Neutral atoms have no charge.

(b) Ions are formed by the transfer of one or more electrons from one atom to another.

(c) A cation is positively charged; an anion is negatively charged. 10. sodium ion: Na

+; calcium ion: Ca

2 +; aluminum ion: A l

3 +; chloride ion: CI"; oxide

ion: O2" ; sulfide ion: S

2~; nitride ion: N

3~; ferrous ion: Fe

2 +; ferric ion: Fe*

+

11. (a) Ionic compounds are formed by the transfer of electrons from one atom to another. In covalent compounds, electrons are shared,

(b) The smallest part of an ionic compound that still has the properties of that compound is a formula unit; the smallest part of a covalent compound that still has the properties of that compound is a molecule.

12. K I : Potassium iodide; ZnO: zinc oxide; AlBr 3: aluminum bromide; C a 3N 2: calcium nitride

13. (a) hydroxide ion, OH"; hydronium ion, H 30+

(b) acetate ion, C2 H 3 0 2" ; bicarbonate ion, HC0 3" (c) phosphate ion, P0 4

3~


1. (d) 8. (c) 2. (c) 9. (c) 3. (b) 10. (a) 4. (a) 11. (d) 5. (b) 12. (d) 6. (b) 13. (b) 7. (a)

FILL-IN QUIZ

1. elements, compounds 2. covalent 3. molecule 4. group number 5. diatomic 6. electronegativity 7. valence

8. "dihydrogen monoxide" 9. cation, anion

10. reduction 11. ionic 12. lost, gained 13. polyatomic ion


1. G) 9. (d) 2. (i) 10. (a) 3. 0) 11. (O 4. (k) 12. (g) 5. (n) 13. (b) 6. (m) 14. (f) 7. (o) 15. (e) 8. (h)

Compounds and chemical change


1. Calculate the molecular weight or formula weight of a compound. 2. Find the percentage composition of a compound. 3. Convert between moles and grams for atoms, ions, and molecules. 4. Differentiate between compounds and mixtures. 5. Relate the law of conservation of mass to a chemical reaction. 6. Balance simple equations by trial and error. 7. Interpret balanced equations in terms of moles. 8. Calculate quantities involved in chemical reactions, given an equation

and the mass of reactant or product. 9. Classify reactions as synthesis, decomposition, substitution, or meta-

thesis. 10. Identify the oxidizing agent and reducing agent in oxidation-reduction

reactions. 11 . Describe the relationship between chemical change and energy. 12. Explain the concept of chemical equilibrium. 13. Describe the factors that affect reaction rates.

STUDY QUESTIONS

1. Give the molecular or formula weights for Na3 P 04 and (NH4 )2 C 03.

28

4

STUDY QUESTIONS

(a) What does a mole of every substance have in common?

(b) How do they vary?

(c) How many grams are in one mole of carbon?

One mole of C 02?

0.10 mole of H2 O?

List three ways in which compounds differ from mixtures.

Give percentage compositions for C 02 and NaCl.

30 COMPOUNDS AND CHEMICAL CHANGE

5. How much mass is gained or lost during a chemical reaction? How is your answer explained by the law of conservation of mass?

6. Balance the following equations:

A1 + A 1 203

N 2H4 + N 2 0 4 ^ N2 + H 2 0

Fe + .H20-> F e 3 04 + H2

7. (a) Write in words what happens in the reaction expressed by the following equation:

c o 2 +H 2 - K : O + H 2O

(b) Write the equation for the following reaction: One mole of nitro-gen molecules reacts with three moles of hydrogen molecules to form two moles of ammonia molecules.

8. How many grams of H2 are needed to form 34 g of NH3 ? (N2 + 3H2

2NH3)

STUDY QUESTIONS 31

9. What are the four major types of chemical reactions? Give an example of each.

10. (a) If a substance is being oxidized, does it lose or gain electrons?

(b) Why is the substance being oxidized called a reducing agent?

(c) If a substance is being reduced, does it lose or gain electrons?

(d) Why is the substance being reduced called an oxidizing agent?

(e) Identify the oxidizing and reducing agents in this equation: Mn + 0 2 -> Mn02

11 . (a) What kind of energy is involved in most chemical reactions?

(b) What is the law of conservation of energy?


13. What are four factors that determine the rate of a reaction?


1. To find the molecular (or formula) weight you add up (a) the negative and positive charges of the ions present (b) the atomic weights of all the atoms (or ions) present in a molecule

(or formula unit) (c) the subscripts of a molecule (or formula unit) (d) the subscripts of a molecule (or formula unit) plus the atomic

weights of the atoms (or ions) 2. In C 0 2, the percentage of carbon by weight is

(a) 73% (b) 40% (c) 60% (d) 27% 3. 0.50 mole of A1(C 2 H3 0 2 ) 3 weighs

(a) 204 g (b) 102 g (c) 150 g (d) 180g 4. Which statement about a compound is true!

(a) It consists of two or more distinct substances. (b) It has no definite composition. (c) Its components cannot be physically separated. (d) The properties of the individual components are retained.

5. Based on the equation 2H2 + 0 2 2H2 O, the mass of water formed (a) is greater than the mass of hydrogen plus oxygen (b) is less than the mass of hydrogen plus oxygen (c) is the same as the mass of hydrogen plus oxygen (d) has no fixed relationship to the mass of hydrogen plus oxygen

12. What happens when a reversible reaction reaches a state of equilibrium?


6. Which equation has been correctly balanced? (a) 2Na3 P 04 + CaCl2 -» Ca3 (P04 ) 2 + NaCl (b) 2Na3 P 04 + 2CaCl2 -> 2Ca3 (P04 ) 2 + 2NaCl (c) 2Na3 P 04 + 3CaCl2 Ca3 (P04 ) 2 + 3NaCl (d) 2Na3 P 04 + 3CaCl2 -+ Ca3 (P04 ) 2 + 6NaCl

7. Which equation fits the following formula: 4 moles of iron react with 3 moles of oxygen to form 2 moles of ferric oxide? (a) 4Fe + 3 02 - ^ 2 F e203

(b) Fe4 + 2 03 ->2Fe2(30) (c) 4Fe + 3 02 - > 3 F e20 (d) Fe4 + 3 02 - > 2 F e203

8. How many g of H2 are needed to form 72 g of H20? (2H2 + 0 2 -+ 2 H20) (a) 16 (b) 4 (c) 8 (d) 2

9. The reaction represented by the equation H 3 P 04 + 3NaOH N a3P 04

+ 3H2 Ï is an example of a (a) synthesis, or combination, reaction (b) decomposition reaction (c) replacement, or substitution, reaction (d) metathesis, or double replacement, reaction

10. The oxidizing agent in a reaction (a) gives up electrons to another substance (b) takes electrons away from another substance (c) is the substance being oxidized (d) neither loses nor gains electrons

11 . During a chemical reaction, there is a (a) conversion of mass to energy (b) loss of energy (c) change of energy from one form to another (d) gain of energy because all reactions give off heat

12. When a state of equilibrium is reached, (a) the rate of the forward reaction equals the rate of the reverse

reaction (b) the forward and reverse reactions stop (c) the rate of the forward reaction is greater than the rate of the

reverse reaction (d) the rate of the reverse reaction is greater than the rate of the

forward reaction 13. The most important factor controlling the rate of a reaction is

(a) temperature (b) the nature of the reactants (c) concentration (d) particle size


FILL-IN QUIZ

1. Water has a molecular weight of amu.

2. In CC1 4, the percentage of C by weight is %.

3. Three moles of H2 0 2 weigh g.

4. If a mixture of iron and sulfur is heated, a new substance, or

, is formed.

5. In every chemical reaction, the total of the reactants

must equal the total of the products.

6. When the equation C 6H1 2 0 6 + 0 2 C 02 + H 2 0 is balanced, there are

oxygen molecules.

7. In an equation, the relative numbers of moles of reactants and products

are given by the

8. In 216 g of water, there are moles.

9. A reaction occurs when iron and oxygen react to

form ferric oxide.

10. During a chemical reaction, an oxidizing agent elec-

trons.

11 . A reaction that absorbs heat is called ; one that

gives off heat is .

12. In a reversible reaction, the direction is more

likely if the reaction is exothermic and if simpler molecules form.

ANSWERS 35

13. A increases the rate of a reaction but remains

unchanged after the reaction.


1. molecular (formula) 7. law of conservation of weight mass

2. mole 8. reducing agent 3. Avogadro's number 9. oxidizing agent 4. mixture 10. equilibrium 5. chemical reaction 11 . catalyst 6. chemical equation

(a) the sum of the atomic weights of all the atoms (or ions) present in the molecule (or formula unit)

(b) two or more substances which have been physically combined but whose atoms have not been joined by chemical bonding

(c) a "shorthand" way of describing the changes that occur in a chemical reaction

(d) a substance which accepts electrons during a chemical reaction (e) a substance that increases a reaction rate but that can be recovered

unchanged at the end of a reaction (0 a law which states that matter is neither created nor destroyed during a

chemical reaction (g) a substance which donates electrons during a chemical reaction (h) a state of balance in which two opposing reactions take place at the

same rate (i) a unit which contains 6.02 × 10

23 particles; a unit whose weight in

grams is equal to the atomic, molecular, or formula weight of the substance

(j) a process by which substances undergo chemical changes, forming new substances with different arrangements of atoms

(k) 6.02 × 1023 ; the number of particles in a mole


1. Na 3P0 4

Composition Number of atoms Atomic weight (amu) Total weight

sodium 3 X 23 69 phosphorus 1 X 31 31 oxygen 4 X 16 64

molecular (formula) weight 164

COMPOUNDS AND CHEMICAL CHANGE

( N H 4) 2C 0 3

Composition Number of atoms Atomic weight (amu) Total weight

nitrogen 2 X 14 28 hydrogen 8 X 1 8 carbon 1 X 12 12 oxygen 3 X 16 48

molecular (formula) weight = 96

2. C0 2

weight of 1 carbon atom =12 weight of 2 oxygen atoms = 32 weight of C0 2 = 44

%C = 12/44 X 100 = 0.27 X 100= 27% % Ο = 32/44 X 100 = 0.73 X 100 = 73%

NaCl weight of 1 sodium ion = 23 weight of 1 chloride ion = 35 weight of NaCl =58

% Na = 23/58 X 100 = 0.40 X 100 = 40% % CI = 35/58 X 100 = 0.60 X 100 = 60%

3. (a) All moles have the same number of particles. (b) Their weights vary, depending on the atomic, formula, or molecular weight of

the substance. (c) 12 g; 12 + 16 + 16 = 44 g; 1 + 1 + 16 = 18 g; 18 g X 0.10 = 1.8 g.

4. Compounds consist of only one substance; mixtures consist of two or more different substances. Compounds have a definite composition; mixtures do not. In a compound the individual properties of the components are lost; in a mixture the individual properties are retained. In a compound the components cannot be physically separated; in a mixture the components can be physically separated.

5. None. The law of conservation of mass states that matter is neither created nor destroyed in a chemical reaction. Thus the total mass of the reactants always equals the total mass of the products.

6. 4Al + 3 0 2 ->2A1 20 3

2 N 2H 4 + N 20 4 -> 3N 2 + 4 H 20 3Fe + 4 H 20 -> F e 30 4 + 4H 2

7. (a) One mole of carbon dioxide molecules reacts with one mole of hydrogen molecules to form one mole of carbon monoxide molecules and one mole of water molecules,

(b) N 2 + 3H 2 -* 2NH3

8. g H 2 = 3 4 g N H 3 x \m o l

° ^ × º

2 g, H* =6 17 g NH 3 2 moles NH 3 1 mole H 2

ANSWERS 37

9. Your examples may vary from those given. The four major types of chemical reactions are synthesis, or combination, (4Fe + 3 0 2 2 F e 20 3) ; decomposition ( 2H 20 -> 2H 2 + 0 2) ; replacement, or substitution, (Fe + 2HC1 FeCl2 + H 2) ; metathesis, or double replacement, (Na2 S 0 4 + BaCl2 -> BaS04 + 2NaCl).

10. (a) It loses electrons. (b) It is called a reducing agent because it gives electrons to another substance,

causing reduction. (c) It gains electrons. (d) It is called an oxidizing agent because it takes electrons from another

substance, causing oxidation. (e) Mn (reducing agent) + 0 2 (oxidizing agent) -* M n 0 2

11. (a) Heat energy is involved in most chemical reactions. (b) The total amount of energy is the same at the beginning and the end of a

chemical reaction; energy can be neither created nor destroyed. 12. The two opposing reactions (forward and reverse) take place at the same speed so

that the quantities of the substances involved remain the same. 13. Factors that determine the rate of a reaction are the nature of the reactants,

concentration, particle size, temperature (and the presence of a catalyst in some cases).


1. (b) 8. (c) 2. (d) 9. (d) 3. (b) 10. (b) 4. (c) 11. (c) 5. (c) 12. (a) 6. (d) 13. (b) 7. (a)

FILL-IN QUIZ

18 8 102

4. compound 5. mass; mass 6. 6 7. coefficients

8. 12 9. synthesis (or combination)

10. gains 11. endothermic; exothermic 12. forward 13. catalyst


1. (a) 7. (f) 2. (i) 8. (g) 3. (k) 9. (d) 4. (b) 10. (h) 5. 0) 11. (e) 6. (c)

Gases and respiration

To demonstrate an understanding of Chapter 5, you should be able to: 1. Describe the "picture" of a gas presented by the kinetic molecular

theory. 2. Use the kinetic theory to explain the diffusion of a gas. 3. Relate temperature to molecular motion. 4. Define pressure and describe its measurement. 5. Describe the relationship between pressure and volume (at constant

temperature). 6. Use the pressure-volume relationship to describe (a) breathing and

(b) the operation of a tank respirator. 7. Describe the relationship between pressure and temperature (at constant

volume). 8. Describe the relationship between volume and temperature (at constant

pressure). 9. Relate the quantity of a gas to (a) pressure and (b) volume.

10. Relate total pressure to the partial pressures of the components in a gas mixture.

11 . Explain respiration in terms of partial pressures. 12. Describe the use of oxygen in respiratory therapy. 13. Identify the properties of three gases and their relation to health.

STUDY QUESTIONS

1. According to the kinetic molecular theory, what does a gas "look" like?

38

5

STUDY QUESTIONS 39

2. According to the kinetic molecular theory, why and how does a gas diffuse?

3. (a) What happens when you heat a gas?

(b) What happens when you cool a gas?

4. (a) What is pressure?

(b) If 250 pounds presses against a square 5 in. long by 5 in. wide, what is the pressure in psi?

5. (a) If the temperature and amount of gas remain fixed, what happens when you increase the pressure? Increase the volume? Decrease the pressure? Decrease the volume?

40 GASES AND RESPIRATION

(b) Write the mathematical formula for the relationship between pres-sure and volume.

6. (a) As you breathe in, increasing the volume of the thoracic cavity, what happens to the pressure in your chest? Why is air then pushed into the lungs?

(b) What happens to the volume and pressure of your chest as you breathe out? Why is air then forced out of the lungs?

7. (a) If the volume remains constant, what happens to the pressure when the temperature is increased? Why?

(b) Why is it dangerous to heat an aerosol can?

8. (a) If the pressure remains constant, what happens to the volume of a gas when the temperature increases?

STUDY QUESTIONS 41

(b) If the pressure remains constant, what is the final volume of a gas heated to 400 K, which occupied 2 liters at 200 K?

9. (a) If volume and temperature remain constant, what happens to the pressure of a gas if the number of moles is decreased?

(b) If the pressure and temperature must remain constant, how can you increase the volume of a gas?

10. (a) What is Dalton's law of partial pressures?

(b) If a gas mixture contains 3 gases with partial pressures of approxi-mately 0.21 atm, 0.78 atm, and 0.28 atm, what is its total pressure?

11 . How does expired air differ from inspired air in terms of the partial pressure of their components?


12. (a) In all forms of oxygen therapy, how does the percentage of oxygen present compare with the percentage of oxygen in the atmosphere?

(b) What are three ways that oxygen therapy can be administered?

(c) What are two hazards of oxygen therapy?

13. (a) How are the following gases used in therapy: carbon dioxide, helium, nitrous oxide?

(b) How would you be alerted of the presence of these poisonous gases: hydrogen sulfide, nitrogen dioxide, carbon monoxide?



1. According to the kinetic molecular theory, the molecules of a gas (a) are constantly moving in a regular pattern (b) are constantly moving in a random manner (c) cannot move because of lack of space (d) move only at high temperatures

2. If the mass of gas A is greater than the mass of gas B, (a) A diffuses more rapidly than Â (b) Â diffuses more rapidly than A (c) they both diffuse at the same rate (d) neither diffuses because they interfere with each other

3. If gas A is heavier than gas Â and they are both heated to the same temperature, (a) the molecules of A move faster than those of Â (b) the molecules of A move more slowly than those of Â (c) the molecules of both gases move at the same rate (d) the molecules move too quickly to determine which are moving

faster 4. The atmosphere

(a) has no pressure (b) has the same pressure throughout (c) has pressure which changes with the altitude (d) has a pressure of 1.47 psi

5. If a gas at constant temperature has an initial pressure of 2 atmospheres and a volume of 3 liters, and its pressure is decreased to 1 atmosphere, the volume (a) remains the same (b) goes up to 6 liters (c) goes down to liter (d) goes down to \ liter

6. As the bellows moves out in an iron lung, the volume increases, causing pressure to (a) increase in the chamber and air to flow into the patient's lungs (b) increase in the chamber and air to flow out of the patient's lungs (c) decrease in the chamber and air to flow out of the patient's lungs (d) decrease in the chamber and air to flow into the patient's lungs

7. If a gas with a pressure of 2 atm is raised in temperature from 100 to 300 K, and the volume remains the same, its pressure (a) is decreased to 1 atm (b) is decreased to \ atm (c) is raised to 3 atm (d) is raised to 6 atm


8.

9.

10.

11 .

12.

13.

FILL-IN QUIZ

1.

Like pressure and temperature, volume and temperature (a) are inversely related (b) are directly related (c) have no relation to each other (d) are sometimes inversely, and sometimes directly, related At standard temperature (273 K) and pressure (1 atm), the volume of 1 mole of gas (a) varies, depending on the gas in question (b) ranges from 22.4 to 760 liters (c) is 22.4 liters no matter what the gas is (d) depends on the number of molecules in the particular mole The sum of the partial pressures of all the gases in a gas mixture (a) is greater than the total pressure (b) is less than the total pressure (c) has no relation to the total pressure (d) is equal to the total pressure During respiration, oxygen flows toward the alveoli because the oxygen partial pressure is (a) lower there than in the air breathed in (b) greater there than in the air breathed in (c) the same as the partial pressure of C 02

(d) the same there as in the air breathed in Which oxygen therapy device uses oxygen at pressures above atmo-spheric pressure? (a) compressed gas cylinder (b) hyperbaric chamber (c) nasal catheter (d) nasoinhaler Nitrogen dioxide is (a) used as an anesthetic (b) used as a respiratory stimulant (c) used to relieve blocked airways (d) not used medically

When gas molecules collide, no is lost.

Molecules in a gas move from a region of concentration

to a region of concentration.

2.

FILL-IN QUIZ 45

3. You must always use the scale when describing

the temperature of a gas.

4. Shoes with thin, pointed heels exert greater pressure because a large

force is applied over a small

air is forced into your lungs.

7. If the volume remains the same, the pressure

when the temperature decreases.

8. If the temperature of a gas is lowered and the pressure remains con-

stant, the volume .

9. The pressure of a gas when the number of moles

is increased (if volume and temperature remain constant).

10. Because has more molecules present than any

other gas in the atmosphere, it exerts the greatest partial pressure.

11 . Respiration depends on differences in

12. In cases of carbon monoxide poisoning or gas gangrene, hyperbaric

therapy, which uses oxygen at pressures than

atmospheric pressure, is used.

5. Pressure is related to volume at constant tem-

perature.

6. When the pressure inside your lungs is than air pressure,


13. Because of its low density, is mixed with oxygen

and administered to patients with blocked airways.


1. kinetic molecular theory 4. partial pressure 2. diffusion 5. respiration 3. pressure 6. hyperbaric therapy

(a) the pressure exerted by one gas in a mixture of gases (b) the spreading out of a substance to fill a volume (c) the theory that describes molecules of a gas as constantly moving in a

random way at very high speeds, often colliding with each other and the walls of their container

(d) the force applied to a certain area (e) oxygen therapy in which oxygen is administered at pressures greater

than atmospheric pressure (f) the exchange of gases within your body and between your body and

the air so that oxygen is delivered to the tissues of the body and carbon dioxide is removed


1. A gas would "look" like mostly empty space-with very small molecules, which are spaced very far apart, moving very rapidly in unpredictable, or random ways. The molecules collide at times, but no energy is lost.

2. A gas diffuses, or spreads out, because its molecules are always in motion. It spreads from a region of high concentration, where there are many molecules, to a region of low concentration, where there are few, until the concentration becomes the same all over.

3. (a) Heating a gas gives the molecules more energy, making them move faster. (b) Cooling a gas takes energy away from the gas, making the molecules move

more slowly. 4. (a) Pressure is the force applied to a certain area.

, , λ n force 2501b 2501b 1Λ A . - x (b) Ρ = = — — Γ : . . = τ- = 10 psi (pounds per square inch)

area 5 in. X 5 in. 25 in . 2

5. (a) The volume of the gas decreases; the pressure of the gas decreases; the volume of the gas increases; the pressure of the gas increases.

0>) ^(initial) X ^(initial) = ^(final) * ^(fmal) 6. (a) The pressure decreases as the volume increases. Air is forced into the lungs

ANSWERS 47

7.

8.

9.

10.

11.

12.

because the pressure of the air outside your body is greater-and a gas always moves from a higher to a lower pressure region,

(b) The volume decreases and the pressure increases. Air is forced out of the lungs because the pressure of the air inside your body is greater than outside.

(a) The pressure is increased because raising the temperature gives the molecules more energy; thus they apply a greater force to the walls of their container.

(b) The volume of the can remains the same, so the pressure must increase, resulting sometimes in the can's exploding.

(a) The volume increases as the temperature is raised.

χ 2 liters 200 Κ \¼) =

V 400 Κ 200 Κ Χ K = 400 Κ Χ 2 liters

V = 4 liters (a) The pressure is also decreased. (b) You can increase the volume by increasing the number of moles (or mole-

cules). (a) The total pressure of a gas mixture is the sum of the partial pressures of all

the gases present. (b) 0.21 + 0.78 + 0.28 = 1.27 atm Expired air has a lower partial pressure of oxygen (Po2) and a higher partial pressure of carbon dioxide (Pco2) than inspired air. (a) The percentage is greater. (b) Oxygen therapy can be administered by a nasoinhaler (or nasal cannula),

nasal catheter, face mask, oxygen tent, or hyperbaric chamber. (c) Oxygen therapy can be toxic when given over long periods of time. High

oxygen concentrations can result in collapse of the alveoli. When given to premature infants, oxygen can cause blindness. The presence of oxygen in high concentration increases the chance of fire.

(a) Carbon dioxide is mixed with oxygen to act as a respiratory stimulant. Helium mixed with oxygen diffuses faster than air and is given to patients with blocked airways. Nitrous oxide is used as an anesthetic.

(b) Hydrogen sulfide has a rotten egg odor. Nitrogen dioxide is brown and irritating. Carbon monoxide cannot be detected easily since it is odorless and colorless. It is produced by incomplete combustion, such as of gasoline in a car engine.


1. (b) 2. (b) 3. (b) 4. (c) 5. (b) 6. (d) 7. (d)

8. 9.

10. 11. 12. 13.

(b) (c) (d) (a) (b) (d)

GASES AND RESPIRATION

FILL-IN QUIZ

1. energy 8. decreases 2. high; low 9. increases 3. Kelvin 10. nitrogen 4. area 11. partial pressures 5. inversely 12. greater 6. less 13. helium 7. decreases


1. (c) 4. (a) 2. (b) 5. (f) 3. (d) 6. (e)

Water


1. Explain the formation of hydrogen bonds in water. 2. Describe the differences between gases, liquids, and solids according to

the kinetic theory. 3. Explain the relatively low vapor pressure of water. 4. Explain the high specific heat of water and its medical importance. 5. Describe the heat changes involved in the conversions between ice,

liquid water, and steam. 6. Define specific gravity and describe its medical application. 7. Relate the following terms: surface tension, cohesion, adhesion, capil-

lary action, meniscus, surfactant. 8. Define viscosity. 9. Describe the factors that affect the pressure of a liquid.

10. Explain the term "water of hydration." 11 . Describe the processes used to purify water. 12. Explain the term "water balance" as it relates to the human body. 13. Describe the use of water in humidity therapy.

49

6

50 WATER

2. (a) Compare the rates of molecular movement in solids, liquids, and gases.

(b) Compare the importance of attractive forces between molecules in solids, liquids, and gases.

STUDY QUESTIONS

1. Why and how do individual water molecules attract each other?

STUDY QUESTIONS 51

(b) Why does water have such a low vapor pressure?

4. (a) How does the specific heat of water compare with other sub-stances?

(b) Why is water used in hot water bottles rather than alcohol?

5. Is heat absorbed or released when liquid water is converted to water vapor? When liquid water is converted to ice? When water vapor is converted to liquid water? When ice is converted to liquid water?

3. (a) What does the vapor pressure of a liquid depend on?

52 WATER

(b) How does a hydrometer work?

7. (a) What causes cohesion in water?

(b) What creates surface tension in water?

(c) Why does water rise in a narrow glass tube? What is this effect called?

(d) What is a meniscus?

6. (a) How does specific gravity differ from density?

STUDY QUESTIONS 53

(e) How does a surfactant work?

8. What does it mean if one liquid is more viscous than another?

9. (a) What two factors affect the pressure of a liquid? How?

(b) Why might an enema bag with a 12-ft tube be dangerous?

10. What is "water of hydration"?

11 . (a) List at least four processes used to purify water.

54 WATER

(b) If you had only a stove, a teapot, a cookie sheet, and a clean container, how might you purify "dirty" water?

12. How does the volume of water taken in by a person compare with the volume eliminated?

13. (a) Why is water added to the oxygen administered to a patient?

(b) What is the purpose of an atomizer or nebulizer?


1. Hydrogen bonding may form by the attraction between (a) one hydrogen atom to another in a water molecule (b) hydrogen and oxygen within a water molecule (c) the oxygen part of one water molecule to the hydrogen part of

another water molecule (d) the hydrogen part of one water molecule to the hydrogen part of

another water molecule. 2. The molecules of a liquid have

(a) more kinetic energy than those of a gas (b) less kinetic energy than those of a gas (c) less kinetic energy than those of a solid (d) the same kinetic energy as those of a solid


3. Water has a relatively low vapor pressure because (a) the attraction between its molecules is low (b) it evaporates more quickly than alcohol (c) hydrogen bonding tends to prevent molecules from escaping the

liquid state (d) its rate of evaporation does not depend on the temperature, as

with other liquids 4. The specific heat of water is

(a) very low (b) very high (c) about the same as most other liquids (d) dependent on how you heat it

5. The amount of heat needed to convert 1 g of a substance from a solid into a liquid at the melting point is the heat of (a) vaporization (b) condensation (c) fusion (d) crystal-lization

6. If a liquid has a specific gravity of 1.01, its density is (a) 10.1 g/ml (b) 1.01 g/ml (c) 1.01 cm

3 (d) 10.1 cm

3

7. The attraction of the molecules of a liquid for another substance is known as (a) cohesion (b) adhesion (c) meniscus (d) surfactant

8. Human blood is (a) less viscous than water (b) of the same viscosity as water (c) more viscous than water (d) too dense to be viscous

9. When pressure is applied to a liquid, the pressure is (a) absorbed by the liquid (b) doubled (c) decreased by half (d) carried unchanged throughout the liquid

10. Which of the following is a hydrate? (a) N a2S 04- 7 H20 (b) N a 2 S 0 4 + 5 H2 0 (c) 7 H20 (d) CaS04, anhydrous

11 . "Hard" water can be softened by (a) letting the calcium or magnesium ions settle out (b) passing it through an ion exchanger (c) chlorination (d) filtration

12. Water balance in the body means that (a) the volume of water taken in equals the volume eliminated (b) the amount of water in the body never varies

56 WATER

tends to keep the molecules from evaporating.

4. The amount of energy needed to raise the temperature of 1 g of water

by l °Cisa

5. The heat of refers to the amount of heat

given off when a liquid is converted to a solid.

6. The of a substance is determined

by dividing its density by the density of water (1.0 g/ml).

7. You should always measure the volume of water in a tube at the

of the meniscus.

8. If the is increased, a substance usually becomes

less viscous.

(c) there is a shortage of water and sodium ions (d) there is an abnormal accumulation of fluid

13. If a patient suffers from high fever, nausea, and diarrhea, a doctor should (a) make sure that water is not added to any gas given to the patient (b) wait for the patient to regain water balance (c) administer some form of humidity therapy (d) keep the room warm to make the patient perspire

FILL-IN QUIZ

1. Hydrogen bonding occurs between the hydrogen "end" of one water

molecule and the "end" of another molecule.

2. The molecules of a solid or liquid move more

than those of a gas.

3. Water has a low vapor pressure because


9. The pressure which a liquid exerts depends on its

and

10. The removal of the water of hydration from a compound is called

11 . Boiling water and condensing the vapor is the basis of a water purifica-

tion technique known as

12. Most excess water in the body is eliminated as _.

13· — measures the amount of water vapor present in a

gas such as air.


1. hydrogen bonding 7. meniscus 2. evaporation 8. surfactant 3. vapor 9. viscosity 4. heat capacity 10. hydrate 5. specific gravity 11 . nebulization 6. surface tension

(a) the unbalanced force at the surface of a liquid caused by the attraction of the molecules below the surface for the molecules at the surface of the liquid

(b) the gaseous form of a substance that normally exists as a liquid or solid (c) a substance which lowers the surface tension of water by reducing the

cohesive force between water molecules (d) the formation of a suspension of very fine particles in a gas (e) a compound which contains a definite proportion of water molecules

acting as single units (f) resistance to flow (g) the mass of a substance compared to the mass of the same volume of

water (at a certain temperature); a measure which has the same numeri-cal value as density but no units

(h) a curved surface caused by unequal forces of attraction by the con-tainer for the molecules of the liquid and attraction of the molecules of the liquid for each other

58 WATER

(i) the quantity of heat needed to increase the temperature of 1 g of a substance by 1°C

(j) the escape of molecules from the surface of a liquid to become the gaseous form of the liquid

(k) the attraction between the partially negative oxygen atom of one molecule and the partially positive hydrogen atom of another molecule


1. The oxygen and hydrogen atoms are covalently bonded, but with unequal sharing of electrons (polar covalent bonding). Thus the oxygen "end" has a slightly negative charge and the hydrogen "end" has a slightly positive charge. The partially negative oxygen "end" of one molecule attracts the partially positive hydrogen "end" of another molecule to the extent that a weak hydrogen bond is formed. Each water molecule forms hydrogen bonds with three or four other molecules.

2. (a) The molecules in solids cannot move around; they only vibrate about fixed positions. The molecules of liquids are in motion but move much more slowly than the molecules of gases,

(b) Because the molecules are so close together, there is a great attractive force between them in a solid, giving it a rigid shape. The attractive force is less great in a liquid, but is strong enough to give it a definite volume and fixed boundaries. There is little or no attractive force between the molecules in a gas.

3. (a) The vapor pressure depends on the attraction between molecules in a liquid; the stronger the attraction, the smaller the tendency to evaporate and the lower the vapor pressure,

(b) Because hydrogen bonding, caused by the strong attraction between mole-cules, tends to prevent the molecules from evaporating, water has a relatively low vapor pressure.

4. (a) Water has a higher specific heat than almost all other substances. (b) Water has a higher specific heat than alcohol. The high specific heat of water

means that much energy must be transferred to change its temperature. Thus a hot water bottle stays hot, and an ice pack stays cool, for a long time.

5. Heat is absorbed; released; released; absorbed. 6. (a) Specific gravity has the same numerical value as density, but it has no units

(unlike density). (b) A hydrometer, like any other floating object, displaces a volume of liquid

with a mass equal to its own mass. Since the hydrometer has a fixed mass, the volume of liquid displaced—and thus how far the bulb sinks—depends on the specific gravity (or density) of the liquid. The hydrometer has marks so that you can measure how far it sinks in a liquid.

7. (a) Cohesion results from the attraction between the water molecules, caused mainly by hydrogen bonding,

(b) Surface tension is created by the unbalanced force at the surface of the water. There are many molecules below the surface attracting the surface molecules, but there are few above.

ANSWERS 59

(c) Because the water molecules are attracted to the inner surfaces of the tube, the water rises; this effect is called capillary action.

(d) A meniscus is a curve in a liquid formed because the surfaces of a container attract the surface of the liquid, as in a glass tube of water, or because the atoms or molecules of a substance have a greater attraction for each other than they do for their container, as in a glass tube of mercury.

(e) A surfactant reduces the cohesive force between water molecules, increasing their ability to "wet" the surface of their container through adhesion.

8. The liquid has a greater resistance to flow, or a greater specific viscosity. 9. (a) Height and density affect the pressure of a liquid. The greater the height of a

column of liquid and the greater its density, the more pressure is exerted, (b) The tube might be raised too high, creating too much pressure in the rectum.

10. Water of hydration is a definite proportion of water molecules contained in certain compounds called hydrates.

11. (a) Processes used to purify water include sedimentation, coagulation, filtration, chlorination, and aeration,

(b) You could heat the "dir ty" water to boiling in the teapot. Holding the cookie sheet over the boiling water, you would let the vapor condense on the cookie sheet and run into the clean container.

12. The volume of water taken in equals the volume eliminated for a normal "water

13. (a) Water is added to prevent irritation of the mucous membranes and dehy-

(b) Atomizers and nebulizers increase the amount of water that air can "hold" by breaking liquid water into tiny particles and suspending them in the air.

balance.'

dration.


1. (c) 2. (b) 3. (c) 4. (b) 5. (c) 6. (b) 7. (b)

8. 9.

10. 11. 12. 13.

(c) (d) (a) (b) (a) (c)

FILL- IN QUIZ

1. oxygen 2. slowly 3. hydrogen bonding 4. calorie 5. crystallization 6. specific gravity 7. bottom (lowest point)

8. 9.

10. 11. 12. 13.

temperature height; density dehydration distillation urine humidity


1. (k) 2. (j) 3. (b) 4. (i) 5. (g) 6. (a)

7. (h) 8. (c) 9. (f)

10. (e) 11. (d)

58 WATER

Solutions


1. Describe the properties of a solution. 2. Explain the process of dissolving for an ionic compound in water. 3. Describe the factors that influence (a) solubility and (b) rate of dissolv-

ing of a solid in a liquid. 4. Relate the terms unsaturated, saturated, and supersaturated. 5. Compare the solubilities of liquids and gases with that of solids in

liquids. 6. Calculate the weight of solute required to prepare a given volume of a

solution of known weight-volume percentage. 7. Calculate the weight of solute required to prepare a given volume of a

solution of known molarity. 8. Carry out problems involving dilution of solutions. 9. Describe the process of osmosis.

10. Relate osmosis to human blood. 11 . Compare colloids with solutions. 12. Describe the process of dialysis and compare it with osmosis.

STUDY QUESTIONS

1. (a) What makes a solution a special kind of mixture?

(b) Name and define the two main parts of a solution.

(c) How does an aqueous solution differ from a tincture?

61

7

62 SOLUTIONS

(b) Why does grease not dissolve in water?

(c) What is an electrolyte?

3. (a) What factors affect solubility?

(b) How can you speed up the rate at which a solid dissolves in a liquid?

4. (a) How does a saturated solution differ from an unsaturated solu-tion?

2. (a) Why and how does sodium chloride dissolve in water?

STUDY QUESTIONS 63

(b) How does a saturated solution differ from a supersaturated solu-tion?

5. (a) What factors determine the amount of gas that can be dissolved in a liquid?

(b) How easily can gases form solutions with each other?

(c) How easily can liquids form solutions with each other?

6. If you are asked to prepare 600 ml of a 0.9% sodium chloride solution, how much sodium chloride would you need?

7. If a solution consists of 0.20 Μ NaCl, how many grams of NaCl does 1 liter of solution contain?

8. If you have available a 10% solution of glucose but need 300 ml of a 0.9% glucose" solution, how much of the 10% solution must you dilute to make the desired solution?

64 SOLUTIONS

(b) What is osmotic pressure? What does the osmotic pressure of a solution depend on?

10. (a) What prevents loss of water from the blood?

(b) What happens if red blood cells are placed in pure water? What is this process called?

(c) What happens if red blood cells are placed in a hypertonic solu-tion? What is this process called?

9. (a) If a semipermeable membrane separates two solutions with differ-ent concentrations, what happens?


11 (a) How does a colloid differ from a solution?

(b) What is the Tyndall effect?

(c) What is Brownian motion?

(d) How does a colloid adsorb another substance?

12. (a) How does dialysis differ from osmosis?

(b) Why must the aqueous solution be changed every two hours during hemodialysis?


1. In a solution, the solvent is (a) the substance being dissolved (b) the major component (c) always a liquid (d) usually a salt

2. When NaCl dissolves in water, the sodium ions are (a) attracted to the oxygen ends of water molecules (b) attracted to the hydrogen ends of water molecules (c) too attracted to the chloride ions to dissolve completely (d) bonded covalently to the water molecules

66 SOLUTIONS

3. To increase the solubility of sugar in water, you must (a) stir the solution vigorously (b) pulverize the sugar particles before adding them to the water (c) heat the solution (d) evaporate the water

4. If a solution contains more sodium chloride than is normally possible at that temperature, it is (a) supersaturated (b) saturated (c) unsaturated (d) insoluble

5. Carbonated water is made by dissolving C 02 in water at a (a) high temperature (b) pressure lower than 1 atm (c) temperature which is gradually increased (d) pressure greater than 1 atm

6. The amount of sodium chloride needed to prepare 400 ml of 0.9% sodium chloride solution is (a) 36 g (b) 0.36 g (c) 3.6 g (d) 360 g

7. Two liters of a solution of 0.50 Μ NaCl contain (a) 58 g of NaCl (b) 29 g of NaCl (c) 8.7 g of NaCl (d) 5.8 g of NaCl

8. If a nurse takes 40 ml of a 10% glucose solution and adds 60 ml of water, the solution is diluted to (a) 24% (b) 4% (c) 0.4% (d) 2.4%

9. If a 2% saline solution is separated by a semipermeable membrane from a 4% saline solution, (a) the salt ions move from the 2% solution to the 4% solution (b) the water molecules move from the 2% solution to the 4% solution (c) the salt ions move from the 4% solution to the 2% solution (d) the water molecules move from the 4% solution to the 2% solution

10. If a patient received water intravenously instead of a normal saline solution, the patient's blood cells would (a) remain the same (b) shrink (c) expand (d) lose their albumin molecules

11 . The particle size is greatest in a (a) solution (b) emulsion (c) sol (d) suspension

12. During hemodialysis, what passes from the blood into the aqueous solution? (a) colloidal particles (b) only the solvent (c) small molecules and ions (d) the large protein molecules of the blood

FILL-IN QUIZ 67

FILL-IN QUIZ

1. The is the substance being dissolved in a solu-

tion.

2. Nonpolar solvents tend to attract and dissolve

solutes.

3. For many solids, the solubility increases as the

increases.

4. If you add more of a solute to a solvent and the solute dissolves, the

solution was .

5. Liquids that dissolve in each other are called ;

those that do not dissolve in each other are .

6. A nurse would need g of NaCl to prepare 700 ml of normal

saline solution (0.9% NaCl).

7. Three liters of a solution of 0.10 Μ NaCl contains g of NaCl.

8. To obtain 200 ml of 7% glucose, you must dilute ml of a 10%

glucose solution.

9. Osmosis is the diffusion of through a

semipermeable membrane.

10. The force which tends to push water and small dissolved substances

into the blood is .

68 SOLUTIONS

11 . Colloids are able to other substances to the

surface of the colloidal particles.

12. During , colloidal particles remain on one side of

a membrane while ions and small molecules move from the more

concentrated to the less concentrated side.


1. solution 8. osmosis 2. solute 9. isotonic 3. solvent 10. colloid 4. dissociation (ionization) 11 . adsorption 5. electrolyte 12. suspension 6. solubility 13. dialysis 7. molarity

(a) the diffusion of a solute across a membrane in the direction of the less concentrated solution

(b) the diffusion of solvent molecules through a membrane in the direction of the more concentrated solution

(c) a homogeneous mixture of one or more substances (d) the separation of a compound into ions (e) the substance which does the dissolving in a solution (f) a substance which produces ions when it dissolves in water (g) having the same osmotic pressure as another solution (h) the number of moles of solute per liter of solution (i) the amount of solute that can be dissolved in a certain amount of

solvent at a particular temperature (j) the substance being mixed or dissolved in a solution (k) a mixture in which one substance is dispersed in another (1) a mixture whose particles are large enough to be seen with the naked

eye (m) the ability of a substance to hold other substances to its surface


1. (a) A solution is homogeneous, having the same properties and composition throughout.

ANSWERS 69

(b) A solution consists of a solvent, the substance that does the dissolving, and a solute, the substance being mixed or dissolved.

(c) Water is the solvent in an aqueous solution. Alcohol is the solvent in a tincture.

2. (a) Water, which is a polar molecule, dissolves other polar substances—both polar covalent molecules and ionic compounds like sodium chloride. Water causes the sodium ions to separate from the chloride ions. The positive ends of the water molecules surround the (negative) chloride anions, while the negative ends of the water molecules surround the (positive) sodium cations. Sodium chloride dissolves completely in water and exists entirely as sodium and chloride ions in solution.

(b) Because grease and other fats are nonpolar, they dissolve only in nonpolar solvents. Water is a polar solvent.

(c) An electrolyte is a substance which produces ions when dissolved in water. 3. (a) The natures of the solute and solvent and temperature affect solubility.

(b) You can speed up the rate by breaking the solid into smaller pieces, stirring, and heating.

4. (a) In a saturated solution, no more solute can be dissolved. In an unsaturated solution, more solute can be dissolved simply by adding more of the solute,

(b) In a saturated solution, there is an equilibrium between the rate of solute dissolving and the rate of solute coming back out of solution. The condition is stable. A supersaturated solution contains more solute than is normally possible at that temperature. It is unstable and readily converts to a saturated solution. (The excess solute crystallizes out of the solution.)

5. (a) The factors include the nature of the gas and liquid molecules, pressure (as the pressure is increased, a gas becomes more soluble), temperature (unlike many solids, gases are less soluble at higher temperatures).

(b) Gases can mix to any extent to form solutions. (c) Some liquids can dissolve in each other to any extent (miscible); others do

not dissolve in each other at all (immiscible). 0.9 g X

6. 100 ml 600 A r=0.54g

7 0.20 mole 58 g = 11.6 g liter mole liter

8. 10%ΧΛ>0.9%Χ 300 ml X = 27 ml

9. (a) The molecules of the solvent move in the direction of the more concentrated solution, diluting i t and raising its level until the difference in height between the two solutions creates enough pressure to stop any further flow of solvent,

(b) Osmotic pressure is the applied pressure needed to keep the levels in two solutions of different concentrations equal. It depends on temperature and the concentration of the solution (the number of ions or molecules of solute).

10. (a) Osmotic pressure, caused largely by the presence of a large molecule, albumin, tends to push water and small dissolved substances, such as waste molecules, into the blood.

SOLUTIONS

(b) Water molecules diffuse into the cells, causing them to expand and burst. This process is called hemolysis.

(c) Water diffuses out of the cells, causing them to shrink. This process is called crenation.

11. (a) The particles in a colloid are much larger; colloids are translucent or opaque, while solutions are transparent.

(b) Though tiny, the particles of a colloid are large enough to reflect and scatter light. You can thus see a beam of light as it passes through a dispersion.

(c) Brownian motion is the random, zig-zag motion caused by collisions of the colloidal particles with the molecules of the dispersing medium.

(d) The particles of the colloid hold smaller particles of another substance to their surfaces.

12. (a) During osmosis, it is the solvent which moves through a membrane. During dialysis, it is the solute which diffuses across the "dialyzing" membrane,

(b) The solution must be changed to prevent the waste products that diffused out of the blood from flowing back into the blood.


1. (b) 7. (a) 2. (a) 8. (b) 3. (c) 9. (b) 4. (a) 10. (c) 5. (d) 11. (d) 6. (c) 12. (c)

FILL- IN QUIZ

1. solute 2. nonpolar 3. temperature 4. unsaturated 5. miscible, immiscible 6. 6.3

7. 17.4 8. 140 9. solvent molecules

10. osmotic pressure 11. adsorb 12. dialysis


1. (c) 8. (b) 2. 0) 9. (g) 3. (e) 10. (k) 4. (d) 11. (m) 5. (f) 12. (1) 6. (i) 13. (a) 7. (h)

Acids, bases, and salts


1. Define an acid in terms of the H+ and OH" concentration of water. 2. Identify common acids by name and formula. 3. Define a base and compare this definition with that of an acid. 4. Identify common bases by name and formula. 5. Explain the meaning of the pH scale. 6. Describe how pH is measured. 7. Explain the process of neutralization and write an equation represent-

ing it. 8. Relate normality to molarity and use normality for titration calcula-

tions. 9. Predict the effect on pH of the hydrolysis of a given salt.

10. Describe the major electrolytes found in the body and their roles. 11 . Explain the functioning of a buffer. 12. Describe the origins and control of acidosis and alkalosis.

STUDY QUESTIONS

1. (a) What is an acid?

(b) What does the strength of an acid depend on?

71

8

72 ACIDS, BASES, AND SALTS

(b) Give the formulas for these acids: hydrochloric acid, sulfuric acid, carbonic acid, acetic acid

3. How does a base differ from an acid?

4. Give the formulas for these bases: ammonia, calcium hydroxide (lime-water), magnesium hydroxide, sodium hydroxide (lye), potassium hydroxide.

5. (a) What does the pH scale measure?

(b) Describe substances with pH readings of 14, 8, 0, 6, 7.

6. (a) What is the purpose of litmus paper?

(b) When might a pH meter be used rather than litmus paper?

2. (a) Give the names of these acids: H N 03, H3 P 04 , H3 B 03 .

STUDY QUESTIONS 73

(b) What is normality?

(c) How does the normality of a solution compare with its molarity?

(d) If you need 10 ml of 0.5 Ν NaOH to titrate 20 ml of an acid solution, what is the normality of the acid?

9. (a) When does hydrolysis occur?

(b) What happens to the pH when NH4 CI is dissolved in water?

(c) What happens to the pH when NaC2 H3 0 2 is dissolved in water?

7. (a) How can you neutralize a base?

(b) How can you neutralize an acid?

(c) Write an equation for the neutralization of water.

8. (a) How is the equivalent weight of an acid found? A base?


10. Give the function of the following electrolytes in the body: Ca2 +

, K+>

HC<V, Mg2 +

.

11 . What does a buffer do? How does it work?

12. (a) What are acidosis and alkalosis?

(d) What happens to the pH when LiN03 is dissolved in water?


(b) Compare the concentrations of bicarbonate ions and carbonic acid in acidosis and alkalosis.

(c) How does the body compensate for respiratory acidosis?


1. The ionization of hydrochloric acid can be shown as (a) HC1->H-+C1

+

(b) 3HC1 + 2 H20 -» 3H2 0+ + 2HC1"

(c) HCl + H 2 0 - > H3 0+ + C r (d) H C l - » H30

+ + C r

2. The correct formula for sulfuric acid is (a) H 2 S 04 (b) HSO; (c) H C2S 04 (d) H 2 S 03

3. When dissolved in water, a base increases the concentration of (a) hydrogen ions (b) hydroxide ions (c) hydrogen mole-cules (d) water molecules

4. Which formula is correct for a base that is extremely important in industry? (a) NH4OH (b) NH3 (c) N(OH)2 (d) NOH

5. If a substance has a pH of 3, it is (a) a weak base (b) a weak acid (c) a fairly strong base (d) a fairly strong acid

6. If litmus paper turns blue when dipped into a solution, the solution is (a) neutral (b) weakly acidic (c) basic (d) strongly acidic

7. A nurse doing a titration to find the concentration of an acid would slowly add, using a buret, a solution of (a) known acid concentration (b) known base concentration (c) unknown acid concentration (d) unknown base concentration

8. A 0.5 Μ solution of H2 S 04 is the same as H2 S 04. (a) 2N (b) IN (c) 0.5 Ν (d) 0.1 Ν

9. The ions C 03

2", HC03", and HP04

2" form solutions that are

(a) acidic (b) neutral (c) basic (d) not hydrolyzed at all


10. Which ion is involved in the blood transport of 0 2 and C 02 ? (a) Na

+ (b) K

+ (c) CI" (d) Ca

2+

11 . If a base enters the blood, a buffer (a) may neutralize it by reacting with H

+ ions

(b) may neutralize it by reacting with OH" ions (c) can do nothing; it only neutralizes acids (d) prevents the base from breaking into ions

12. If someone excretes alkaline urine after taking too many antacids, the person may be suffering from (a) respiratory acidosis (b) metabolic acidosis (c) respiratory alkalosis (d) metabolic alkalosis

FILL-IN QUIZ

1. The hydra ted hydrogen ion (H3 0+) is called the

ion.

2. , H C 2 H 3 02 , is an organic acid based on carbon.

3. acts as a base in water even though it contains no

hydroxide ion.

4. The formula for calcium hydroxide is .

5. If a substance has a pH of 12, it is a

6. If a solution is strongly acidic, it will turn the color of litmus paper

7. The reaction of an acid with a base is called .

8. Normality shows the number of of solute in 1

liter of solution.


9. When ammonium chloride dissolves in water, the solution becomes

10. The primary extracellular cation in the body, , main-

tains osmotic pressure and water balance in blood and tissue spaces.

11 . A neutralizes the small amounts of acid or base

added to your system.

12. occurs when there is an increase in the bicar-

bonate ion in the blood.

KEY WORD MATCHING QUIZ L a c id

7. normality \

% b a se 8. equivalent weight

3·

s a lt 9. hydrolysis

4. indicator 10. acidosis 5. neutralization H, alkalosis 6. titration

(a) a substance that raises the hydroxide ion concentration of water (b) an ionic compound which results from the chemical reaction of an acid

with a base (c) a dye whose solution is colored, which can be used to measure the pH

of a solution (d) the number of equivalents in 1 liter of solution (e) a condition in which the pH of the blood is lower than 7.35 (f) the weight in grams that will provide 1 mole of hydrogen ions (for an

acid) or hydroxide ions (for a base) (g) a substance that raises the hydrogen ion concentration of water (h) the reaction of an acid with a base (i) a procedure in which a solution of known base or acid concentration is

slowly added to an acid or base until it is neutralized (j) the reaction of a salt with water, changing the pH from the neutral

value (k) a condition in which the pH of the blood is greater than 7.45

78 ACIDS. BASES, AND SALTS


1. (a) An acid is a substance that forms hydrogen ions when it is dissolved, raising the hydrogen ion concentration of water. Thus the number of hydrogen ions becomes larger than the number of hydroxide ions,

(b) The strength of an acid depends on how completely it is ionized in solution; the more an acid ionizes, the stronger it is.

2. (a) nitric acid, phosphoric acid, boric acid (b) HC1, H 2S 0 4, H 2C 0 3, H C 2H 30 2

3. When an acid dissolves, i t increases the number of hydrogen ions. When a base dissolves, it increases the number of hydroxide ions, and thus the number of hydroxide ions becomes greater than the number of hydrogen ions.

4. NH 3, Ca(OH)2, Mg (OH)2, NaOH, KOH 5. (a) The pH scale measures the concentration of hydrogen (or hydronium) ions in

solution. (b) strong base, weak base, strong acid, weak acid, neutral

6. (a) Litmus paper indicates whether a substance is acidic or basic by changing color from red to blue. Red indicates a fairly strong acid; blue indicates a relatively strong base,

(b) A pH meter is used when more exact measurements are needed. 7. (a) You can neutralize a base by reacting it with an acid.

(b) You can neutralize an acid by reacting it with a base. (c) H + + OH"-> H 20 (or H 30 + + OH~-* 2H 20)

8. (a) The equivalent weight of an acid is found by dividing the weight of 1 mole by the number of hydrogens in the molecule that can react with a base. The equivalent weight of a base is found by dividing the weight of 1 mole by the number of hydroxide ions in the formula unit (or the number of protons the base can react with).

(b) Normality is the number of equivalents in 1 liter of solution. (c) The normality of a solution is always greater than or equal to its molarity. (d) NX 20 ml = (0.5 Ν) X 10 ml

^ = ( 0 . 5 A Q ( 1 0 m l ) = 0 2 5 20 ml

9. (a) Hydrolysis occurs whenever one of the ions of a salt can react with water to form a weak acid or a weak base.

(b) The pH goes below 7, indicating that the solution is acidic. (c) The pH goes above 7, indicating that the solution is basic. (d) The pH remains the same.

10. Ca2+ provides the framework for bones and teeth and is needed for blood clotting and muscle activity. K + maintains osmotic pressure in the cells and is needed for nerve and muscle activity. HC03~ acts as a buffer, maintaining the acid-base balance of blood. Mg 2+ is needed for enzyme activity and for the neuromuscular system.

11. A buffer maintains an almost constant pH by neutralizing small amounts of acid or base that are added to the body's system. The buffer consists of two parts so that it can react with either an acid or a base, thus maintaining the normal pH.

12. (a) Acidosis is a condition in which the pH level drops below 7.35. Alkalosis is an increase in the blood pH above 7.45.

ANSWERS 79

(b) In acidosis, there is either a decrease in the bicarbonate ion concentration or an increase in carbonic acid concentration. In alkalosis, there is either an increase in the bicarbonate ion concentration or a decrease in carbonic acid concentration.

(c) The nervous system responds by increasing the depth and rate of breathing so that the partial pressure of carbon dioxide in the lungs is decreased. Carbonic acid breaks down, reducing its concentration in the blood, and the resulting carbon dioxide is exhaled.


1. (c) 2. (a) 3. (b) 4. (b) 5. (d) 6. (c)

7. (b) 8. (b) 9. (c)

10. (c) 11. (b) 12. (d)

FILL-IN QUIZ

1. hydronium 2. acetic acid 3. ammonia 4. Ca(OH)2

7. 8. 9.

10. 11. 12.

Na+

buffer alkalosis

neutralization equivalents acidic

5. (strong) base 6. red

KEY TERM MATCHING QUIZ

1. (g) 2. (a) 3. (b) 4. (c) 5. (h) 6. (i)

7. (d) 8. (f) 9. (j)

10. (e) 11. (k)

Nuclear chemistry and radiation


1. Define radioactivity and describe its three forms. 2. Complete and interpret a given nuclear equation. 3. Describe the process of natural radioactive disintegration. 4. Discuss methods of artificially preparing radioisotopes. 5. Calculate the remaining activity of a known amount of radioisotope of

given half-life after a specified amount of time. 6. Compare the processes of fission and fusion. 7. Describe the process of exposure and development of photographic

film. 8. Explain the operation of the following radiation detectors: Geiger-

Muller tube, dosimeter, film badge, thermoluminescent dosimeter, scintillation counter.

9. Define the following units of radiation: curie, roentgen, rad, dose equivalent, lethal dose.

10. Describe the use of radioisotopes in medical diagnosis. 11 . Discuss the application of radiation therapy to cancer. 12. Explain the effects of exposure to radiation on the human body. 13. List steps you can take to minimize exposure to radiation.

STUDY QUESTIONS

1. (a) What is radioactivity?

80

9

STUDY QUESTIONS 81

2. Complete the following nuclear equation and explain what takes place: 2

U R a - +2| | Rn

3. What is a radiation disintegration series?

4, (a) What happens during neutron capture?

(b) What happens during transmutation?

5. (a) If you have 100 micrograms fag) of a radioisotope with a half-life of 120 days, how many micrograms of the radioisotope would you have left after 240 days?

(b) Why is a short half-life important in medical applications?

(b) How do the three forms of radiation differ from each other?

82 NUCLEAR CHEMISTRY AND RADIATION

7. How is photographic film exposed and developed?

8. (a) How does a Geiger-Muller counter work?

6. How does fission differ from fusion?

STUDY QUESTIONS 83

9. What do the following units of radiation measure: curie, roentgen, rad, dose equivalent, lethal dose?

10. Why are radioisotopes used in medical diagnosis?

(b) How does a scintillation counter work?


13. What steps can you take to minimize exposure to radiation?

11 . (a) What effect does radiation have on cancer cells? On normal cells?

(b) What does the success of radiation therapy depend on?

12. How does overexposure to radiation affect the genetic material? A developing fetus? Blood-forming tissue of the bone marrow?



1. Beta radiation consists of (a) small particles having zero charge (b) electrons (c) particles that have two protons and two neutrons (d) particles that have two protons and two electrons

2. 2

&Po-> + 2 H e (a) 2gi Pb (b)

2gjPb (c)

2g2

3Pb (d) 2gf Pb

3. According to present theory, the beta particle results from (a) the valence shell giving off an electron (b) a proton being converted to a neutron (c) a neutron being converted to an electron (d) a pion being converted to an electron

4. If a stable element undergoes neutron activation, the resulting radio-active isotope (a) cannot be readily separated from the stable form of the element (b) is said to be carrier-free (c) can be easily separated by elution (d) converts to the radioactive isotope of another element

5. If 12.5 ì% of a radioisotope remain out of 50 ìg after 12 hours have passed, the half-life of the radioisotope is (a) 24 hours (b) 12 hours (c) 6 hours (d) 3 hours

6. Fission and fusion are similar in that both (a) involve the splitting of a heavy nucleus (b) require extremely high temperatures (c) occur when a nucleus is bombarded by neutrons (d) release tremendous amounts of energy

7. Photographic development is carried out in a dark room to prevent (a) complete exposure by ordinary light (b) the film from becoming a negative (c) the film from turning completely light (d) the silver bromide from becoming radioactive

8. Which of the following can be used to survey a room for radiation? (a) Geiger counter (b) dosimeter (c) film badge (d) scintillation counter

9. Which unit applies to all types of radiation and takes into account the energy received by the exposed tissue? (a) curie (b) rad (c) roentgen (d) half-life

10. After technetium-99m is administered, an abnormality in the brain may be shown by (a) no radiation given off (b) radiation given off where none should be present


(c) a "cold" spot (d) the radioimmunoassay test

11 . Radiation destroys (a) cancer cells but not normal cells (b) normal cells but not cancer cells (c) both normal cells and cancer cells (d) neither normal cells nor cancer cells

12. Radiation damage first shows up in (a) the muscle tissue (b) those cells that divide infrequently (c) the nervous tissue (d) those cells that divide most rapidly

13. Paper acts as a shield against (a) alpha particles (b) beta particles (c) gamma rays (d) no form of radiation

FILL-IN QUIZ

1. An alpha particle consists of the nucleus of a

atom.

2. 2

|oTh breaks down to form 2

1 | Ra and

3. All isotopes of the elements having atomic weights greater than bismuth

are naturally

4. The process in which a nucleus is changed to the nucleus of another,

radioactive element is

5. If you have 40 ì% of a radioisotope with a half-life of 100 minutes,

after 300 minutes you would have Mg of the radioisotope.

6. The nuclear reaction of two light elements to form a heavier one is

called

7. After being developed, a film is placed in a

prevent the whole picture from turning black.

to


8. Based on the same principle as a Geiger counter, a

is used to measure a single dose of radiation.

9. The measures the quantity of absorbed

radiation on a common scale for different types of radiation.

10. A radioactive isotope of is administered when

examining the thyroid gland.

11 . If more cells are destroyed than

cells, radiation therapy for cancer would be

considered unsuccessful.

12. Radiation sickness occurs when a person is overexposed to

radiation.

13. You need lead or concrete shielding to protect yourself from


1. radiation 2. radioactivity 3. alpha radiation 4. beta radiation 5. gamma radiation 6. nuclear reaction

7. radioisotope 8. transmutation 9. half-life

10. ÷ ray 11 . teletherapy 12. half-thickness

(a) a form of radiation which is generated when a beam of electrons strikes a metal plate in an evacuated tube

(b) particles or energy given off by the nucleus of an unstable atom (c) the process of nuclear decomposition in which particles or energy are

given off (d) particles that have two protons and two neutrons (e) the transformation of a stable nucleus into the nucleus of another


element by hitting the nucleus with protons, neutrons, or other small particles

(0 the time required for the decay of one-half of a given number of radioactive nuclei

(g) the thickness in millimeters (mm) needed to absorb one-half the radia-tion emitted

(h) the irradiation of a cancer site with ÷ rays or with gamma rays from an external source

(i) electrons given off at high speed and energy (j) rays with extremely high energy (k) a process in which the protons and neutrons of atoms are rearranged (1) a radioactive isotope


1. (a) Radioactivity is the process of nuclear decomposition or disintegration in which the nuclei of unstable atoms break down, giving off particles or energy,

(b) Alpha radiation consists of alpha particles, which have two protons and two neutrons. Because of their large size, they are easily stopped and do not even penetrate the skin. Beta radiation contains electrons given off with high speed and energy. Beta particles can penetrate the skin but are stopped before reaching any internal organs. Gamma radiation consists not of particles but of high energy rays (no mass or charge) which can penetrate deeply into the body and cause serious damage.

2. 2

H Ra-* 2 He+ 2liRn Radium breaks down into radon, releasing an alpha particle.

3. A radioactive disintegration series is a chain of reactions in which a radioactive isotope naturally disintegrates until a stable isotope forms.

4. (a) During neutron capture, a stable nucleus is bombarded with neutrons, form-ing a radioactive isotope of that element and causing the emission of gamma rays.

(b) During transmutation, a stable nucleus is bombarded with small particles (protons, neutrons, alpha particles). The nucleus is changed into a nucleus of a different element, which is radioactive.

5. (a) 25 Mg (b) A short half-life means that the radioactive isotope will lose its radioactivity

in a short time and thus will do less damage. 6. Fission involves the "splitting" of a heavy atomic nucleus into two or more pieces

by hitting it with a neutron. Additional neutrons are formed, creating a chain reaction. Fusion involves the reaction of two light elements to form a heavier one and requires extremely high temperatures (over 1,000,000°C). Fusion releases even more energy than fission.

7. When an χ ray or light strikes the silver bromide on the film, it knocks out an electron, producing a silver ion (Ag+). The exposure occurs only where the light or radiation can reach. The film is developed by converting the silver ions to a black form of silver metal (in a dark room). The film contains silver and is thus dark in

ANSWERS 89

the regions where the light or radiation passed through and is light where the radiation or light was absorbed. It is a negative, giving a reverse image of the true picture.

8. (a) A Geiger counter consists of a metal tube filled with molecules of gas under low pressure. The tube is connected to a source of electric current. When radiation enters the window in front of the tube, it ionizes the gas, allowing it to conduct electricity. This current is amplified and shows up in the move-ment of a needle on the meter or in a clicking sound. The greater the swing of the needle or the faster the clicking, the more radiation is present,

(b) A scintillation counter contains a crystal which gives off flashes of light (scintillations) when hit by radiation. A counting device electrically records and amplifies the scintillations.

9. A curie measures the activity of a radioisotope; 1 curie (Ci) equals the rate of decay of 1 g of radium. A roentgen measures the exposure of gamma or χ rays. A rad is the dose of radiation actually absorbed. A dose equivalent measures the quantity of absorbed radiation on a common scale for different types of radiation. The units of dose equivalent are rems (roentgen equivalent for "man"). The lethal dose is the amount of radiation that kills 50% of those exposed within 30 days.

10. Radioisotopes are used because the atoms can be located, using a radiation detec-tor. Thus a physician can determine if parts of an organ are not functioning properly, or can discover pathological conditions in the blood, the bones, and the lungs.

11. (a) Radiation destroys cancer cells but usually destroys normal cells as well. (b) The success of radiation therapy depends to a large degree on the relative

rates of tissue repair in normal cells compared to cancer cells. 12. Overexposure to radiation leads to a decrease in the white blood cells, increasing

the danger of infection, and a decrease in the blood platelets and red cells, increasing the danger of hemorrhaging or anemia. Overexposure also causes changes in the molecules of the genetic material, leading to offspring with mutations. If a developing fetus is exposed to radiation, it may abort, become malformed, or develop leukemia.

13. To minimize exposure to radiation, you should try to stay at least 3 feet away from radioactive materials; spend as little time near radioactive materials as possible; protect yourself with shielding, special clothing, or rubber gloves. Also do not eat, drink, or smoke when working where radioactive materials are handled; have your film badge or other detector and your blood count checked regularly;and dispose of wastes in special containers.


1. (b) 8. (a) 2. (c) 9. (b) 3. (d) 10. (b) 4. (a) 11. (c) 5. ( 0 12. (d) 6. (d) 13. (a) 7. (a)

NUCLEAR CHEMISTRY AND RADIATION

FILL-IN QUIZ

1. helium 2. ^He 3. radioactive 4. transmutation 5. 5 6. fusion 7. stop bath

8. dosimeter 9. dose equivalent

10. iodine 11. normal; cancer 12. ionizing 13. gamma rays


1. (b) 7. (1) 2. (c) 8. (e) 3. (d) 9. (f) 4. (i) 10. (a) 5. 0) 11. (h) 6. (k) 12. (g)

Organic chemistry— hydrocarbons


1. Relate the electronic structure of carbon to its ability to form bonds. 2. Write the names and structural formulas of the first six alkanes. 3. Name the alkyl groups formed from the first six alkanes. 4. Draw structural isomers based on a given molecular formula. 5. Describe the chemical reactivity of alkanes. 6. Write the names and structural formulas of alkenes with up to six

carbon atoms. 7. Relate the reactivity of alkenes to their chemical structure. 8. Write the names and structural formulas of alkynes with up to six

carbon atoms. 9. Write the names and structural formulas for cycloalkanes with up to six

carbon atoms. 10. Describe the bonding in benzene. 11 . Relate the reactions of benzene to its structure. 12. Recognize polynuclear aromatic hydrocarbons and their carcinogenic

properties.

STUDY QUESTIONS

1. (a) How many valence electrons does carbon have? How many bonds is it thus able to form? What kinds of bonds can it form?

91

10

92 ORGANIC CHEMISTRY-HYDROCARBONS

(b) What is the significance of carbon's ability to form bonds with itself?

2. (a) Draw the structural formula and the condensed structural formula for methane, propane, and hexane.

(b) Given names for the following alkanes: CH3 CH3, CH3 CH2 CH2 CH3, CH3 CH2 CH2 CH2 CH3.

3. (a) How does an alkyl group differ from an alkane?

STUDY QUESTIONS 93

(a) What are isomers?

(b) Draw the structure for 2,3-dimethylbutane

(c) What is the name of this isomer? CH3 CH2 CH CH2—CH3

CH3

Do alkanes react with other substances? Explain.

(b) List the first six alkanes and the alkyl groups formed from them.


6. (a) Give the condensed structural formulas for ethene, butene, and pentene.

(b) Give the names for CH2 =CHCH3 and CH2 =CHCH2 CH2 CH2 CH3.

7. Why are alkenes more reactive than alkanes?

8. (a) Give the condensed structural formula for ethyne, pentyne, and 3-hexyne.

(b) Give names for the following: CH^CCH3 and CH^CCH2CH3 .

9. Draw the structural formulas of cyclopropane and cyclohexane.


10. What is unusual about the double and single bonds in a benzene molecule?

11 . How and why do the reactions of benzene differ from those of an alkene?

12. (a) What is a polynuclear aromatic compound?

(b) Draw the structure of benzpyrene and list two places where it is found.


1. Carbon forms (a) 2 ionic bonds (b) 2 covalent bonds (c) 4 ionic bonds (d) 4 covalent bonds

2. The correct condensed structural formula for ethane is (a) CH2CH3 (b) C 3 H C 3 H (c) CH3CH3 (d) CH3CH2

3. The condensed structural formula CH3 CH2 CH2 — represents (a) propyl group (b) propane (c) butyl group (d) butane


4. The name for

CH3

I

CH3— C CH2 CH3

CH3

is (a) 2,2-methylbutane (b) 2-2,methylbutane (c) 2-2,dimethylbutane (d) 2,2-dimethylbutane

5. When an alkane burns completely, it forms (a) carbon monoxide and water (b) carbon dioxide and water (c) carbon and pentane (d) carbon dioxide and carbon monoxide

6. The structural formula for propene is (a) CH=CH-CH3 (b) CH2=CH-CH3

(c) C H 3= C H2- C H3 (d) C H 2= C H2- C H3

7. Because an alkane has a double bond it is considered (a) hydrated (b) unsaturated (c) dehydrated (d) saturated

8. The correct structural formula for 2-pentyne is (a) CH^CCH2CH2CH3 (b) C H 3- C = C - C H2- C H3

(c) C H3^ C H3- C H2 (d) C H - C ^ C - H2 - C H2 - C H3

9. A cycloalkane consists of (a) a straight chain of carbon atoms with two or three hydrogen

atoms attached to each carbon (b) a ring of carbon atoms with two hydrogen atoms connected to

every carbon atom (c) a ring of carbon atoms with three hydrogen atoms connected to

every carbon atom (d) a ring of alkane molecules joined together

10. Each bond in a benzene molecule is considered (a) more than a double bond, less than a triple bond (b) a double bond (c) a single bond (d) more than a single bond, less than a double bond

11 . Benzene undergoes substitution reactions rather than addition reactions because its ring structure is (a) extremely unstable (b) saturated (c) very stable (d) unsaturated

12. A polynuclear aromatic hydrocarbon is made by fusing together at least (a) two benzene rings (b) two cycloalkanes (c) three alkyl groups (d) two alkynes

FILL-IN QUIZ 97

3. CH3— is the condensed structural formula for.

4. The correct name for C H 3- C H2- C H2- C H - C H3 is

CH-a

5. The reaction of an alkane with is called combus-

tion.

6. is represented by the structural formula

CH2

=CHCH2 CH3.

7. Alkenes can react with hydrogen molecules to form

8. The correct structural formula for propyne is .

9. has five carbon atoms in a ring with two hydro-

gen atoms attached to each carbon atom.

10. The bonding of benzene is typical of all com-

pounds.

11 . Benzene undergoes reactions rather than addi-

tion reactions.

12. is a dangerous carcinogen found in the "tar" of

cigarette smoke.

FILL-IN QUIZ

1. Because carbon has valence electrons, it forms covalent

bonds.

2. The correct condensed structural formula for propane is



1. organic chemistry 2. inorganic chemistry 3. hydrocarbon 4. structural formula 5. alkane 6. alkyl group 7. isomer

8. alkene 9. unsaturated

10. saturated 11 . alkyne 12. cycloalkane 13. aromatic hydrocarbon 14. carcinogenic

(a) cancer-producing (b) an alkane that has a ring structure (c) made up of single bonds (d) the study of compounds of carbon (e) a "diagram" showing how the atoms are arranged in a molecule (0 an organic compound in which the number of hydrogen atoms is always

two more than twice the number of carbon atoms (g) the study of compounds that do not contain carbon (h) a compound composed of carbon and hydrogen atoms only (i) an "incomplete" molecule consisting of an alkane with one hydrogen

atom removed (j) a molecule which has the same molecular formula as another molecule,

but which has a different structure (k) having a double bond, allowing the molecule to pick up two more

atoms in an addition reaction (1) hydrocarbon with a triple bond between two carbon atoms (m) a hydrocarbon which contains a double bond between two carbon

atoms (n) a hydrocarbon, such as benzene, which has partial double bond charac-

ter in its ring structure


1. (a) Carbon has four valence electrons and thus can form four covalent bonds. It can form four single bonds, two double bonds, two single bonds and one double bond, or one triple bond and one single bond,

(b) By bonding with itself, carbon can form long chains or rings of carbon atoms. 2. (a) methane Η

C H4 H - C - H I Η

propane Η Η Η CH3CH2 CH3 H - C - C - C - H

Η Η Η

ANSWERS 99

hexane Η Η Η Η Η Η CH 3 CH2 CH2 CH2 CH2 CH3 H - C - C - C - C - C - C - H

Η Η Η Η Η Η (b) ethane, butane, pentane

3. (a) An alkyl group differs from its alkane by having one less hydrogen atom. If cannot exist by itself but must combine with an atom that takes the place of the hydrogen atom,

(b) methane methyl ethane ethyl propane propyl butane butyl pentane pentyl hexane hexyl

4. (a) Isomers are molecules that contain the same number of atoms but have different structures and thus different properties.

(b) C H 3- C H - C H - C H 3

CH3 CH3

(c) 3-methylhexane 5. Alkanes are fairly inert and do not react with other substances under normal

conditions, except for oxygen. They burn, or combust, very easily. Lighter fluid and gasoline are examples of alkanes.

6. (a) ethene CH 2=CH 2

butene CH2=CHCH2CH3 (one of several possible isomers) pentene CH2=CHCH2CH2CH3 (one of several possible isomers)

(b) propene (propylene), hexene 7. Alkenes are more reactive because the presence of a double bond lets an alkane

molecule pick up two more atoms during an addition reaction. 8. (a) ethyne CH^CH

pentyne CH^CCH2CH2CH3

3-hexyne C H 3- C H 2- C = C - C H 2- C H 3

(b) propyne, butyne 9. cyclopropane

CH2

H2 C CH2

cyclohexane

^CH2 CH 2^

CH2— CH2

10. All the bonds in benzene are chemically the same. The electrons of the double bonds spread out, so to speak, over all six carbon atoms so that each bond is more than a single bond but less than a double bond.

11. Benzene replaces hydrogens with other groups in substitution reactions, rather than addition reactions typical of the alkenes. It does so because its ring system is very stable.


12. (a) A polynuclear aromatic compound consists of molecules formed by the fusing together of at least two benzene rings,

(b) Benzpyrene is found in cigarette "tar," heavily charcoaled meats, and the air of large cities.


1. (d) 7. (b) 2. ( 0 8. (b) 3. (a) 9. (b) 4. (d) 10. (d) 5. (b) 11. (c) 6. (b) 12. (a)

FILL-IN QUIZ

1. four; four 2. CH 3CH 2CH 3

3. methyl group 4. 2-methylpentane 5. oxygen 6. butene

7. alkanes 8. CH^CCH3

9. cyclopentane 10. aromatic 11. substitution 12. benzpyrene


1. (d) 8. (m) 2. (g) 9. (k) 3. (h) 10. (c) 4. (e) 11. (1) 5. (f) 12. (b) 6. (i) 13. (n) 7. 0) 14. (a)

Oxygen derivatives of the hydrocarbons

To demonstrate an understanding of Chapter 1 1, you should be able to:

1. Describe the role of a functional group in an organic molecule. 2. Identify alcohols based on a structural formula. 3. List two common alcohols and their uses. 4. Describe the chemical reactions of alcohols. 5. Identify ethers from a structural formula and list two examples with

their uses. 6. Discuss the reactions of ethers. 7. Identify aldehydes from structural formulas and list two examples with

their uses. 8. Describe the clinical application of the oxidation of aldehydes. 9. Identify ketones from structural formulas and list two examples with

their uses. 10. Identify carboxylic acids from structural formulas and list two

examples with their uses. 11 . Describe the reactions of carboxylic acids and compare with inorganic

acids. 12. Identify esters from structural formulas and list two examples with

their uses. 13. Write equations for the formation and hydrolysis of esters.

101

11

102 OXYGEN DERIVATIVES OF THE HYDROCARBONS

2. Give (a)

the common and systematic names for CH3OH

(b) CH3CH2CH2OH

(c) CH3CH2CH2CH2OH

(d) CH3CH2OH

(e) CH3CH2CH2CH2CH2OH

3. (a) How is ethyl alcohol used medically?

(b) How is isopropyl alcohol used medically?

4. What two kinds of chemical reactions are common for alcohols?

STUDY QUESTIONS

1. What is a functional group and what does it do?

STUDY QUESTIONS 103

5. Give the common names and medical uses for C H3C H2- 0 — C H2- C H3

and C H2= C H - 0 - C H = C H2.

6. (a) How reactive are ethers in general?

(b) Why should ethers be treated carefully?

7. (a) Give the common names and functions of two aldehydes.

Ï Ï II II

(b) Give the common and formal names for H—C—Ç and CH3CH.

8. How can you test for the presence of an aldehyde?

9. Give the formal and common names for the following and tell how they are used:

Ï

(a) CH3CCH3 (b) CH3

104 OXYGEN DERIVATIVES OF THE HYOROCARBONS

12. (a) Give the common names for HC-OCH3 and CH3C-OCH2CH3

(b) How are esters commonly used?

13. (a) Write an equation showing the hydrolysis of methyl acetate.

(b) Write an equation showing the esterification of acetic acid and methyl alcohol.


1. All functional groups must combine with (a) only one hydrocarbon group (b) more than three hydrocarbon groups (c) one or more hydrocarbon groups (d) two or more hydrocarbon groups

10. (a) What is a carboxyl group?

Ï Ï II II

(b) Give the common and formal names for HC—OH and CH3C—OH.

11 . What happens when a carboxylic acid reacts with a base?


2. CH3 CH2 CH2 OH is the formula for (a) propyl alcohol (b) amyl alcohol (c) butyl alcohol (d) methyl alcohol

3. A patient in shock might feel better after receiving (a) ethyl alcohol (b) methyl alcohol (c) isopropyl alcohol (d) menthol

4. When an alcohol is dehydrated it forms (a) an aldehyde (b) an acid (c) an alkene (d) a ketone

5. The common name for CH3—O—CH 3 is (a) diethyl ether (b) dimethyl ether (c) "ether" (d) divinyl ether

6. When an ether oxidizes, it forms (a) an aldehyde (b) a peroxide (c) an alkene (d) an alcohol

7. An aldehyde used as a preservative and a germicide is (a) paraldehyde (b) benzaldehyde (c) acetaldehyde (d) formaldehyde

8. If an aldehyde is placed in Benedict's solution, it reacts to form (a) cuprous oxide and an acid (b) cuprous oxide and a base (c) copper and carbon dioxide (d) copper and an acid

Ï II

9. CH3CCH2CH3 represents (a) methyl propyl ketone (b) diethyl ketone (c) dimethyl ketone (d) ethyl methyl ketone Ï

II 10. CH3 CH2 C-OH is the structural formula for

(a) ethanoic acid (b) propanoic acid (c) butanoic acid (d) methanoic acid

11 . A carboxylate group consists of (a) an oxygen atom double bonded to a hydrogen atom (b) a carbon atom double bonded to a hydroxyl group (c) the carboxyl group minus the hydrogen ion (d) a hydrogen atom double bonded to a carbon atom

Ï II

12. CH3C-OCH2CH2CH3 is the structural formula for (a) methyl propionate (b) ethyl formate (c) ethyl acetate (d) propyl acetate

13. When an ester is hydrolyzed, the end products are (a) water and a base (b) an acid and water (c) an acid and an alcohol (d) an acid and a base


7. The group, which consists of a carbon atom

double-bonded to an oxygen atom, is found in all aldehydes.

8. Urine can be tested for the presence of sugar, which contains an

aldehyde group, by placing it in solution.

Ï II

9. The common name for CH3 CCH3 is

10. acid, which plays an important role in the break-

down of sugars in your body, is found in certain fruits.

11 . When a carboxylic acid reacts with a base, it forms a salt and

12. Ethyl alcohol and acetic acid react to form water and.

13. is the reverse reaction of esterification.

FILL-IN QUIZ

1. A influences the properties of the

hydrocarbon group to which it is attached.

2. is the systematic name for CH3 OH.

3. is an alcohol used in skin softeners and supposi-

tories.

4. When oxidized, primary alcohols first form and

then organic acids.

5. C H 3C H 2- 0 - C H3 is the formula for

6. Ethers slowly oxidize to form highly explosive

ANSWERS 107


1. functional group 7. carbonyl group \

3 1 0 0 1 1 01 8. carboxyl group

3. hydroxyl group 9. ester 4' e i h er

10. esterification 5. aldehyde n> hydrolysis 6' k e t o ne

12. saponification

(a) a substance made up of molecules that contain a hydroxyl group connected to a hydrocarbon group

(b) a substance made up of molecules in which carbon is double-bonded to an oxygen atom and single-bonded to a hydrogen atom, leaving only one bond available for a hydrocarbon group

(c) a functional group formed by combining a carbonyl group and a hydroxyl group

(d) a substance made up of molecules in which carbon is double-bonded to an oxygen atom and in which two hydrocarbon groups are attached on either side of the carbonyl group

(e) the synthesis of an ester (f) the product of the reaction of a carboxylic acid with an alcohol (g) a group made up of carbon double-bonded to oxygen (h) a chemical reaction in which water is added in the presence of a

catalyst, causing a bond to break (i) an arrangement of atoms which cannot stand alone, but which controls

the properties of the molecule in which it is located (j) —OH, a functional group consisting of one oxygen and one hydrogen

atom (k) a substance made up of molecules that contain an oxygen atom cova-

lently bound to two hydrocarbon groups (1) a reaction in which a strong base and an ester react to form a salt and

an alcohol


1. A functional group is an arrangement of atoms which exist in molecules in combination with one or more hydrocarbon groups. The functional group controls the properties of the molecule.

2. (a) methyl alcohol, methanol (b) propyl alcohol, propanol (c) butyl alcohol, butanol (d) ethyl alcohol, ethanol (e) amyl alcohol, pentanol

3. (a) Ethyl alcohol may be administered to help patients overcome shock or collapse. It is also used as a solvent for medicines and as a disinfectant or antiseptic.

(b) Isopropyl alcohol is used for sponge baths and massages.


4. Alcohols undergo oxidation reactions, in which oxygen is added or hydrogen removed, and dehydration reactions, in which the alcohol loses the hydroxyl group and a hydrogen atom.

5. Diethyl ether ("ether") and divinyl ether ("vinethene") are both used as anes-thetics.

6. (a) Ethers are relatively stable and usually do not react with acids, bases, or active metals.

(b) Ethers should be treated with care because of their tendency to oxidize to peroxides, which are very explosive.

7. (a) Formaldehyde is used as a germicide and as a preservative that hardens muscle tissues. Paraldehyde is used to depress the central nervous system and to desensitize the gums of the mouth. Benzaldehyde is used to make drugs, dyes, perfumes, and flavors,

(b) formaldehyde, methanal; acetaldehyde, ethanal 8. You can add the substance to a solution that contains an oxidizing agent. If a

reaction occurs, the substance is an aldehyde. Ah example is Benedict's solution. 9. (a) Propanone (acetone, dimethyl ketone) is used as a solvent and in nail polish

removers. (b) Acetophenone (methyl phenyl ketone) is used as a hypnotic, inducing sleep.

10. (a) A carboxyl group is a combination of a carbonyl group and a hydroxyl group, (b) formic acid, methanoic acid; acetic acid, ethanoic acid

11. When a carboxylic acid reacts with a base, a salt, made up of the anion of the acid plus the cation of the base, and water are formed.

12. (a) methyl formate, ethyl acetate (b) Esters are usually used for flavorings and fragrances.

Ο Ο 13. (a) C H 3 C - O C H 3 + H 20 - » C H 3C - O H + HOCH3

(b) The equation would be the reverse of the one you wrote for part (a).


1. (c) 8. (a) 2. (a) 9. (d) 3. (a) 10. (b) 4. (c) 11. (c) 5. (b) 12. (d) 6. (b) 13. (c) 7. (d)

FILL - IN QUIZ

1. functional group 2. methanol 3. glycerol 4. aldehydes 5. ethyl methyl ether 6. peroxides 7. carbonyl

8. Benedict's 9. acetone (or dimethyl ketone)

10. citric 11. water 12. ethyl acetate 13. hydrolysis

ANSWERS 109


1. 0) 2. (a) 3. (j) 4. (k) 5. (b) 6. (d)

7. (g) 8. (c) 9. (f)

10. (e) 11. (h) 12. (1)

Other organic derivatives and polymers

12


1. Identify halogen derivatives of hydrocarbons from structural formulas and list two examples of alkyl halides with their uses.

2. Identify sulfur derivatives of hydrocarbons. 3. Identify amines and list two examples with their uses. 4. Explain why amines are basic and describe the formation of quaternary

ammonium salts. 5. Describe how amides and sulfonamides are formed. 6. Identify nitrogen heterocycles based on 5- or 6-membered rings. 7. Identify alkaloids and list two examples with their uses. 8. Identify nitrates, nitrites, nitriles, and compounds containing the nitro

group. 9. Define polymer, plastic.

10. Identify addition polymers and list two examples with their uses. 11 . Identify condensation polymers and list two examples with their uses.

STUDY QUESTIONS

1. Give the names and functions of the following alkyl halides:

CI OH

(a) C l - C - C -H

CI OH*

110

STUDY QUESTIONS 111

(b) CF 3CH2CCH2CF 3

(c) CH2=CHC1

(d) C F 2= C F2

2. What is CH3 SH and how does it differ from methyl alcohol?

3. Give the names and functions for two of the following amines:

CH2—CH—NH, I

2

CH3

(b) CH3N CH2 CH2 CI

CHj CH2 CI

(c) NH2CH2CH2SH

(d)

112 OTHER ORGANIC DERIVATIVES AND POLYMERS

4. (a) Why are amines basic?

(b) How is a quaternary ammonium salt formed?

5. (a) How are amides formed? Draw the amide group.

(b) Draw the sulfonamide group.

6. Name the following: (a)

STUDY QUESTIONS 113

Ç

7. (a) What is an alkaloid?

(b) What are the medical uses of codeine.

8. Draw three functional groups that contain both nitrogen and oxygen. Give their names.

9. (a) What is a polymer?

(b) What is a plastic?

10. Give the names and functions of two of the following, (a) { C H 2- C H2} „

(b) ΓÇ2 CH

—

(c) -[CH2-CHCl}„ (d) -£CF2-CF2} „



1. is an example of an alkyl chloride. (a) NaCl (b) CHC13 (c) C F 2= C F2 (d) KC1

2. If "thio" appears in the name of a compound, you know that the compound contains a functional group based on (a) oxygen (b) hydrogen (c) a halogen (d) sulfur

3. An amine consists of (a) a hydrocarbon in which halogens take the place of hydrogen

atoms (b) a hydrocarbon which contains sulfur instead of oxygen (c) a carboxyl acid group combined with a halogen (d) an ammonia molecule in which one to three hydrogens are

replaced by hydrocarbon groups 4. In a quaternary ammonium salt, nitrogen is surrounded by four

(a) oxygen atoms (b) sulfur atoms (c) chlorine atoms (d) carbon atoms

Ï II

5. HC—NH2 represents (a) methanamide (b) ethanamide (c) propanamide (d) methylacetamide

is called

Ç

(a) pyrrole (b) pyridine (c) purine (d) pyrimidine 7. Which of the following is not an alkaloid?

(a) procaine (b) codeine (c) cocaine (d) morphine 8. Amyl nitrite contains the following functional group:

(a) - N 02 (b) -ÏÍÏ (c) - O N 02 (d) - C ^N 9. Which of the following is true?

(a) All polymers are plastics. (b) All plastics are polymers. (c) A plastic is never a polymer. (d) A polymer is never a plastic.

10. Which of the following is not an addition polymer? (a) Orion (b) nylon (c) polyethylene (d) Teflon

11 . Name two condensation polymers and tell how they are used.


11 . Which of the following is not a condensation polymer? (a) Melmac (b) Bakelite (c) Teflon (d) Dacron

FILL-IN QUIZ

1. When a halogen is substituted into an alkane, the resulting molecule is a

2. When two thiols are oxidized, a is formed.

3. contain the amino functional group plus the

carboxylic acid group.

4. The unshared pair of electrons, or , of an amine

can bond with a hydrogen ion.

5. An amine reacts with a to form an

amide.

6. A is a ring containing two or more different

kinds of atoms.

7. is an alkaloid found in coffee beans and tea

leaves.

8. The functional group - O N 02 is found in .

9. Monomers linked together form a .

10. The polymer formed by the addition of molecules of ethylene is called

11 . Two condensation polymers used in making fibers are

and .



1. alkyl halide 6. heterocycle 2. sulfhydryl group 7. alkaloid 3. amine 8. polymer 4. quaternary ammonium salt 9. plastic 5. amide 10. crosslink

(a) a molecule in which a halogen is substituted into an alkane (b) a chemical bond between the chains of a polymer (c) a nitrogen-containing organic molecule of vegetable origin, usually with

a heterocyclic ring system (d) any material based on an organic substance of high molecular weight

that is solid in its final form but has been shaped by flow at some stage in its manufacture

(e) a substituted ammonia molecule in which one or more hydrocarbon groups replace one or more hydrogen atoms

(f) a large molecule made by the linking together chemically of many small molecules

(g) a functional group with the formula —SH (h) a compound in which a nitrogen atom is bonded to four carbon atoms (i) a product of the reaction of an amine with a carboxylic acid (j) a ring containing two or more different kinds of atoms


1. (a) Chloral hydrate is used to induce sleep and prevent convulsions. (b) Hexafluorodiethyl ether (Flurothyl, Indoklon), which produces convulsions,

is used as a substitute for electroshock therapy. (c) Vinyl chloride is used in making plastics; it is now thought to be related to

certain types of cancer. (d) Tetrafluorethylene is used to make Teflon.

2. CH3SH, methanethiol or methyl mercaptan, has a sulfur atom in the place of the oxygen atom of methyl alcohol (CH3OH).

3. (a) Amphetamine (benzedrine) is a central nervous system stimulant. (b) Mechlorethamine (nitrogen mustard) is used in cancer therapy. (c) Cysteamine (2-aminoethanethiol) reduces the effect of radiation if given

before exposure. (d) Para-aminobenzoic acid (PABA) is used in suntan products to prevent ultra-

violet radiation from burning the skin. 4. (a) Amines are basic because they contain an unshared pair of electrons (lone

pair) which can bond to a hydrogen ion. The proton it thus gains gives the nitrogen a positive charge,

(b) Quaternary ammonium salts are formed when an amine reacts with an alkyl halide so that the hydrocarbon group occupies the fourth position on the nitrogen atom.

ANSWERS 117

5. (a) Amides are formed by the reaction of an amine with a carboxylic acid. - C - N \

6. (a) pyrimidine (b) pyridine (c) pyrrole 7. (a) An alkaloid is a nitrogen-containing molecule of vegetable origin, usually with

a heterocyclic ring system, (b) Codeine is used to suppress coughing and kill pain.

8. nitrite -ΟΝΟ nitrate - O N 0 2

nitro —N0 2

9. (a) A polymer is a very large molecule made up of smaller molecules, or units called monomers, which are chemically linked together,

(b) A plastic is any material based on an organic substance of high molecular weight that is solid in its final form but has been shaped by flow at some stage in its manufacture.

10. (a) Polyethylene is used in squeeze bottles, film, tubing, etc. (b) Orion is used in clothing. (c) Polyvinyl chloride is used in film, insulation, tubing, and fibers. (d) Teflon is used to reduce sticking in frying pans.

11, Any two of the following are correct, nylon—fibers and molded articles Dacron-fibers and films Bakelite—electric components Melmac—dishware

Ο

(b)

Ο


1. (b) 2. (d) 3. (d) 4. (d) 5. (a) 6. (c)

7. (a) 8. (b) 9. (b)

10. (b) 11. (c)

FILL - IN QUIZ

3. amino acids 4. lone pair

1. alkyl halide 2. disulfide

7. 8. 9.

10. 11.

caffeine nitrates polymer

5. carboxylic acid 6. heterocycle

polyethylene nylon; Dacron


KEY W O R D M A T C H I N G Q U I Z

1. (a) 6. (J) 2. (g) 7. (c) 3. (e) 8. (f) 4. (h) 9. (d) 5. (i) 10. (b)

Carbohydrates


1. Define carbohydrate and give the classification according to size. 2. Identify monosaccharides according to the number of carbons and

location of the carbonyl group. 3. Relate the open and closed forms of monosaccharides. 4. Draw the structure of glucose, describe its role in the body, and explain

how its presence is determined. 5. Identify galactose and fructose. 6. Identify the disaccharides maltose, lactose, and sucrose; state their

relation to health. 7. Describe the structure and importance of starch, glycogen, and cellu-

lose. 8. Relate the following terms to reactions of carbohydrates: (a) reducing

sugar, (b) glycoside, (c) phosphate ester, (d) fermentation. 9. Describe the relationship between optical isomers.

STUDY QUESTIONS

1. (a) What is a carbohydrate?

119

13

120 CARBOHYDRATES

(b) How are monosaccharides, disaccharides, oligosaccharides, and polysaccharides related?

2. (a) What would a 5-carbon monosaccharide with an aldehyde group be called?

(b) What would a 6-carbon monosaccharide with a ketone group be called?

3. (a) How do the closed forms of monosaccharide differ from the open form?

(b) How is the alpha form of the closed chain converted to the beta form?

4. (a) Draw the straight chain form of glucose.

STUDY QUESTIONS 121

(c) What happens when glucose is added to Benedict's solution?

5. (a) How does galactose differ from glucose?

(b) How do the properties of fructose compare with the other sugars?

6. For the following disaccharides, tell what units they are made up of, where they are found naturally, and how they are used or misused, (a) maltose

(b) lactose

(c) sucrose

(b) What role does glucose play in the body?

122 CARBOHYDRATES

(b) In what form are carbohydrates stored in your body? Why is this form well suited for storage?

(c) Why cannot cellulose be digested in your body? What role does it play in your body?

8. (a) What is a reducing sugar?

(b) How are glycosides and phosphate esters formed?

7. (a) What is starch made up of? What role does it play in the diet?


(c) What happens during alcoholic fermentation?

9. (a) How are optical isomers, or enantiomers, related to each other?

(b) How significant is it to your body whether a molecule has the D or L configuration?


1. The largest carbohydrates are called (a) polysaccharides (b) oligosaccharides (c) monosaccharides (d) disaccharides

2. A 3-carbon monosaccharide is a (a) triose (b) tetrose (c) hexose (d) pentose

3. Two forms of a monosaccharide that are isomers are known as (a) hemiacetals (b) furanoses (c) anomers (d) mutarota-tions

4. Most glucose molecules in solution exist in (a) the open form (b) the closed beta form (c) the closed alpha form (d) equal amounts of the three forms

5. Which of the following pairs are epimers? (a) glucose and fructose » (b) glucose and sucrose (c) galactose and fructose (d) galactose and glucose

6. Invert sugar consists of fructose and (a) maltose (b) lactose (c) sucrose (d) glucose

124 CARBOHYDRATES

7. The most abundant organic substance found in nature is (a) starch (b) glycogen (c) cellulose (d) dextran

8. Sugars in which the aldehyde group can be oxidized to a carboxylic acid group are called (a) glycosides (b) glucosides (c) reducing sugars (d) phos-phate esters

9. Natural monosaccharides have (a) the L configuration (b) the D configuration (c) an equal mixture of the D and L configurations (d) more of the L than D configuration

FILL-IN QUIZ

1. usually consist of two to ten

monosaccharides bonded together.

2. A(n) is a monosaccharide with four car-

bon atoms and an aldehyde group.

3. Conversion between the alpha and beta forms by way of the open form

is called

4. provides the major source of energy for life.

5. Glucose isomers which differ only in the arrangement of groups at a

single carbon atom are called .

6. is a disaccharide made up of glucose and galac-

tose.

7. When you digest starch, it is eventually broken down by hydrolysis into

molecules.

8. are formed by the reaction of a sugar with a

nonsugar.

ANSWERS 125


1. carbohydrate 7. hemiacetal 2. polysaccharide 8. hydrocolloid 3. monosaccharide 9. glycoside 4. disaccharide 10. fermentation 5. mutarotation 11 . optical isomers 6. reducing sugar

(a) two monosaccharides joined by a chemical bond (b) a large carbohydrate polymer (c) a compound formed by the addition of an alcohol to an aldehyde group (d) molecules that are mirror images (e) a polysaccharide that forms a colloid when dispersed in water (0 the decomposition of a carbohydrate by the enzymes of a living

organism (g) a compound formed by the reaction of a monosaccharide at the

hemiacetal group (h) conversion between the alpha and beta forms of a monosaccharide. (i) a carbohydrate that is readily oxidized because it contains a reactive

aldehyde (or ketone) group G) an organic molecule containing carbon, hydrogen, and oxygen (k) the simplest carbohydrate unit


1. (a) A carbohydrate is an organic molecule that contains carbon, hydrogen, and oxygen. It consists of one or more polyhydroxyl ketone or aldehyde units,

(b) All are made up of the monosaccharide unit. Monosaccharides are only one such unit; disaccharides are made up of two monosaccharide units. Oligosaccha-rides generally consist of two to ten units, and polysaccharides consist of many monosaccharides bonded together.

2. (a) aldopentose (b) ketohexose 3. (a) In the closed forms, carbon-1 no longer forms an aldehyde group. Instead, it

contains an ether linkage to carbon-4 and a hydroxyl group, in addition to a bond to another carbon and a hydrogen atom,

(b) The alpha form is converted to the open chain, which is then converted to the beta form of the closed chain (mutarotation).

9. The optical isomers of a chiral molecule are called

126 CARBOHYDRATES

CH I

H-C-OH I

H O - C - H I

H-C-OH I

H-C-OH I CH2OH

(b) Normally found in your blood stream, glucose provides the major source of energy for life.

(c) When glucose is added, the aldehyde group is oxidized to a carboxylic acid group, while the cupric ion (Cu

2 +) is reduced to the cuprous ion (Cu

+). The

products are gluconic acid and an insoluble solid (CuO). The amount of glucose present affects the color of Benedict's solution, changing the original blue color to green, yellow, orange, or red.

5. (a) Galactose differs from glucose only in the arrangement of groups at a single carbon atom (carbon-4).

(b) Fructose is the most water soluble sugar. It is also the sweetest sugar. 6. (a) Maltose consists of two glucose units joined by an oxygen atom. It'is found in

sprouting grain and used in baby formulas and other beverages. (b) Lactose consists of glucose and galactose units joined by an oxygen atom. It*is

found in milk and is used as a nutrient. Milk should not be given to people who digest lactose poorly.

(c) Sucrose consists of glucose and fructose units joined by an oxygen atom. It'is found in sugar cane, sugar beets, and most fruits and vegetables. Called "table sugar," it is used as a sweetner. Some doctors feel that eating too much sugar can lead to diabetes mellitus and heart disease. Sugar promotes tooth decay.

7. (a) Starch is a mixture of amylose, a straight-chain glucose polymer, and amylopec-tin, a highly branched polymer. Starch is the most important carbohydrate you eat and thus forms the basis for your diet.

(b) Carbohydrates are stored as glycogen. The large size of this molecule prevents it from diffusing through the cell walls.

(c) Cellulose cannot be digested by people because it consists of beta-glucose units. Your enzymes can only hydrolyze the bonds between alpha-glucose units. It provides roughage, stimulating the movement of food in the intestinal tract and aiding in the formation of normal stools.

8. (a) A reducing sugar is one in which the aldehyde group can be oxidized to a carboxylic acid group.

(b) Glycosides are formed by the reaction of a sugar with a nonsugar, usually a compound with a hydroxyl group or nitrogen heterocycle. Phosphate esters are formed by the reaction of phosphoric acid with the hydroxyl group of a sugar.

(c) During alcoholic fermentation, the enzymes of a living organism decompose certain sugars to ethyl alcohol and carbon dioxide.

9. (a) Optical isomers, or enantiomers, are mirror images of each other. They cannot be superimposed.

ANSWERS 127

(b) It is very significant. The enzymes of your body recognize only one enantiomer of a molecule. Similarly, a drug must have the proper configuration to be able to carry out its designed role.


1. (a) 6. (d) 2. (a) 7. (c) 3. (c) 8. (c) 4. (b) 9. (b) 5. (d)

FILL-IN QUIZ

1. oligosaccharides 2. aldotetrose 3. mutarotation 4. glucose 5. epimers

6. lactose 7. glucose 8. glycosides 9. enantiomers


1. (J) 7. (c) 2. (b) 8. (e) 3. (k) 9. (g) 4. (a) 10. (0 5. (h) 11. (d) 6. (i)

Lipids


1. Describe the structure of a fatty acid and identify those which are known as essential.

2. Describe the structure and properties of soaps and detergents. 3. Describe the structure and use of waxes. 4. Write an equation for the formation of a triacylglycerol (fat), and

compare the properties of fats and oils. 5. Write equations for the hydrolysis and saponification of triacylglycerols

(fats). 6. Discuss the role of depot lipid in the body. 7. Identify phospholipids and explain their importance. 8. Describe the composition of the cell membrane and compare the

process of active transport to diffusion. 9. Explain how sphingolipids differ from triacyl glycerols.

10. Identify the steroid ring structure and discuss the role of cholesterol.

STUDY QUESTIONS

1. (a) Describe the structure of a fatty acid.

(b) How does a saturated fatty acid differ from an unsaturated fatty acid?

(c) List the two essential unsaturated fatty acids.

128

14

STUDY QUESTIONS 129

(b) How does soap get greasy hands clean?

(c) Why were detergents invented?

(d) What have been two problems associated with detergents?

(a) What is wax?

(b) What are the medical uses of lanolin and beeswax?

(a) Write an equation showing the reaction of glycerol and stearic acid [CH3(CH2)1 6-COOH] to form tristearin.

(b) List four ways in which fats differ from oils.

(a) What is a soap and how is it made?

(a) Write an equation showing the hydrolysis of triolein (oleic acid H3 3C 1 7COOH).

(b) Write an equation showing the saponification of tristearin.

How are depot lipids used by the body?

(a) Name two phospholipids found in the body.

(b) What roles do phospholipids play in the body?

(a) What makes up a cell membrane?

132 LIPIDS


(b) How does active transport differ from diffusion?

9. How do sphingolipids differ from triacylglycerols?

10. (a) Describe the steroid ring structure.

(b) What role does cholesterol play in the body?

(c) How is cholesterol related to hypertension and gall bladder prob-lems?


1. In most fatty acids, the carbons are arranged in a (a) ring (b) straight chain, with a carboxylic acid group in the middle (c) branched chains, with a carboxylic group at the center (d) straight chain, with a carboxylic acid group at one end

132 LIPIDS

2. A soap molecule (a) is nonpolar (b) is polar (c) has a nonpolar end and a polar end (d) becomes nonpolar in solution

3. The wax used to make dental impressions is (a) beeswax (b) cerumen (c) lanolin (d) carnauba wax

4. Which characteristic is not true for oils? (a) mostly vegetable origin (b) liquid at room temperature (c) saturated (d) high iodine number

5. Saponification is a reaction in which a triacylglycerol reacts with a strong base to form (a) glycerol and three soap molecules (b) glycerol and three water molecules (c) three fatty acid molecules and water (d) oleic acid and water

6. Which function does fat not perform in the body? (a) reserve supply of energy (b) insulation against the cold (c) maintenance of stable pH in blood (d) protection of organs

7. Phospholipids differ from triacylglycerols in that one of the hydroxyl groups of glycerol is esterified with (a) phosphorus (b) phosphoric acid (c) phosphoglyceride (d) phosphatidyl choline

8. In active transport (a) no energy is expended (b) molecules are carried from a region of low concentration to one of

greater concentration (c) only water molecules pass through the membrane (d) the process takes place as in diffusion

9. Sphingolipids (a) contain glycerol (b) are based on an amino acid (c) are based on an amino alcohol (d) contain no amino acids or alcohols

10. If a person suffers from hypertension, it is likely that cholesterol will be present (a) inside the walls of the arteries (b) in the gall bladder

FILL-IN QUIZ 133

2. Detergents made of carbon atoms in straight chains can be broken

down by microorganisms and are thus considered

3. A wax derived from wool is called

4. Fats are esters formed from and

5. The hydrolysis of a fat or oil is the exact reverse of the

reaction.

6. Fat stored in the body is found in tissue.

7. Because they have a polar "head" and a nonpolar "tail," phospholipids,

like detergents, act as agents.

8. Active transport is an energy requiring process in which molecules are

moved across a cell membrane in the direction opposite to

9. Sphingolipids are based on , an amino alcohol.

10. Unlike the other lipids discussed in this chapter, steroids are not

(c) in the cell membranes (d) inside the bone marrow

FILL-IN QUIZ

1. The two essential unsaturated fatty acids are and

134 LIPIDS


(a) (b) (c)

(d)

(e) (f)

(g)

(h)

(i)

ω (k) (1) (m)

(n)

1. 2. 3. 4. 5. 6. 7.

lipid fatty acid prostaglandin soap detergent wax fat

8. oil 9. depot lipid

10. phospholipid 11 . active transport 12. sphingolipid 13. glycolipid 14. steroid

a synthetic molecule containing a polar end and a nonpolar end the product of the reaction of a fatty acid with a strong base a substance differing from a triacylglycerol in that one of the hydroxyl groups is esterified with phosphoric acid instead of a fatty acid a fatty acid containing 20 carbon atoms, with a cyclic structure in part of the molecule the ester of a fatty acid with a high molecular weight alcohol a molecule consisting of a 12 to 20 carbon atom chain with a carbox-ylic acid group at one end an organic compound found in plants or animals that dissolves in nonpolar solvents an energy-requiring process which moves molecules across a membrane in the direction opposite to diffusion an ester formed from fatty acids and glycerol a vegetable fat a lipid that is based on the amino alcohol sphingosine fat stored in the body, primarily as triacylglycerols a lipid which is not an ester, but which consists of molecules built around a framework of four saturated hydrocarbon rings fused together. a sphingolipid that contains a carbohydrate attached to a sphingosine


1. (a) Most fatty acids consist of 12 to 20 carbons arranged in a straight chain, with a carboxylic acid group at one end of the molecule.

(b) Saturated fatty acids have only single bonds between the carbon atoms, while unsaturated fatty acids can have up to four double bonds in the molecule.

(c) linoleic acid; linolenic acid 2. (a) A soap is the carboxylate salt of a fatty acid, made by reacting a fatty acid

with a strong base. (b) The nonpolar part of the soap molecule dissolves the nonpolar grease. The

ionic end of the soap molecule, which is attracted to the water, pulls the grease away and disperses it in the water.

ANSWERS 135

(c)

(d)

(a) (b)

Detergents were invented for use in hard water. Soap forms insoluble curds instead of suds in hard water. Some detergents were not biodegradable and created buildup of foam in waterways. Detergents also contained phosphates which may encourage the growth of algae (eutrophication). A wax is an ester of a fatty acid with a high molecular weight alcohol. Lanolin is used as a base for ointments. Beeswax is used in making impres-sions of teeth.

CH2 OH Ο

Ο II

0Η2 Ο C—C17H35

Ο (a) CHOH + 3 C 1 7H 3 5 C - O H - * C H - 0 - 0 - C 1 7H 3 5 + 3 H 20

CH2 OH Ο II

C H 2- 0 - C - C 1 7H 35

[Note that C 1 7H 3 5— is the same as CH 3(CH 2) 1 6- . ]

(b) fats oils

mostly animal origin solid at room temperature saturated low iodine number

mostly vegetable origin liquid at room temperature unsaturated high iodine number

Ο II

CH2 —O—C—Ci7H33

Ο CH2OH Ο II I II

(a) C H - 0 - C - C 1 7H 33 + 3H 2 Ο CHOH + 301 7Η3 3Ο-ΟΗ

Ο CH2 OH II

C H 2- 0 - C - C 1 7H 33

0» ? C H 2- 0 - C - C 1 7H 35

Ο CH2 OH Ο II I II

C H - 0 - C - C 1 7H 35 + 3KOH -> CHOH + 3C 1 7H 3 5C-Cr + Κ

Ο CH2OH II

C H 2- 0 - C - C 1 7H 3 5

Depot lipids are used by the body for energy, for insulation (protection against the cold or heat loss from the body), and for protection of organs against injury.

7. (a) phosphatidyl choline (lecithin); phosphatidyl ethanolamine (cephalin) (b) Phospholipids bring water-insoluble lipids into contact with water-soluble

proteins and other substances. They also are involved in transporting fatty acids in the blood. Their major role is in forming cell membranes.

8. (a) A cell membrane is made up of two rows of phosphoglyceride molecules arranged so that the polar "heads" are on the outside of the membrane and the nonpolar "tails" are in the middle. Mixtures of phosphoglycerides are found in the membrane,

(b) Active transport is an energy-requiring process that moves molecules across the cell membrane in the direction opposite to diffusion. Large molecules (proteins) in the membrane carry across molecules, which could not pass through by diffusion, from a region of lower concentration to one of greater concentration.

9. Sphingolipids do not contain glycerol; they are based on the amino alcohol sphingosine.

10. (a) The steroid ring structure consists of molecules based on a framework of four saturated hydrocarbon rings fused together.

(b) Cholesterol is used to synthesize steroid hormones and other such molecules. It forms part of myelin, the stable membrane that coats the nerve cells.

(c) Deposits of cholesterol inside the walls of the arteries can lead to hyper-tension. Cholesterol is also present in gallstones, which are abnormal deposits from bile in the gall bladder.


1. (d) 6. (c) 2. (c) 7. (b) 3. (a) 8. (b) 4. (c) 9. (c) 5. (a) 10. (a)

FILL-IN QUIZ

1. linoleic; linolenic 2. biodegradable 3. lanolin 4. fatty acids; glycerol 5. esterification 10

6. adipose 7. emulsifying 8. diffusion 9. sphingosine

esters


1. (g) 8. 0) 2. (f) 9. (1) 3. (d) 10. (c) 4. (b) 11. (h) 5. (a) 12. (k) 6. (e) 13. (n) 7. (i) 14. (m)

132 LIPIDS

Proteins


1. Identify those features common to amino acids. 2. Describe the properties of amino acids with regard to (a) optical config-

uration, (b) charge, (c) diet. 3. Define protein, draw the structure of a polypeptide, and explain the

meaning of the term "primary structure." 4. Compare the two main types of protein secondary structure. 5. Explain the factors that maintain the tertiary structure of a protein. 6. Compare the structure and function of collagen and hemoglobin. 7. Classify proteins according to shape and solubility, and according to

function. 8. Write an equation for the hydrolysis of a polypeptide. 9. Define denaturation and describe two denaturating agents and their role

in medicine. 10. Describe the composition of bones and teeth.

STUDY QUESTIONS

1. What structural features do amino acids have in common?

137

15

(a) What is the optical configuration of the chiral amino acids in your body?

(b) What happens when an amino acid is put in a neutral solution?

(c) Why are some amino acids considered essential? List three essen-tial amino acids.

(a) What is a protein?

(b) Draw part of the structure of a polypeptide, labeling the peptide bonds.

(c) What does the primary structure of a protein show?

132 LIPIDS

STUDY QUESTIONS 139

5. (a) How is the tertiary structure of a protein maintained?

(b) Why are disulfide bonds stronger than hydrophobic bonds?

6. (a) How is the structure of collagen related to its function?

4. What are the two main types of secondary structure and how do they differ?

140 PROTEINS

7. (a) What is the shape of a globular protein? Is it soluble in water?

(b) Give the functions of the following proteins: contractile proteins, hormones, transport proteins.

8. Write an equation showing what happens when the dipeptide Gly-Val is hydrolyzed.

(b) What is the function of hemoglobin? How does the heme group of a hemoglobin molecule help it function?


9. (a) What happens to the structure of a protein when it is denatured?

(b) How do alcohol and iodine "work" as disinfectants?

10. (a) What are bones made of? Why is this a good combination?

(b) What are teeth made of? Why are teeth harder than bones?

(c) How are teeth and bones formed?


1. The number of major amino acids found in proteins is (a) 5 (b) 10 (c) 20 (d) 40

2. The chiral amino acids in the body have (a) the D configuration (b) equal proportions of the L and D configurations (c) the L configuration (d) more of the D configuration than the L configuration

3. If a single amino acid out of many hundreds is changed, the properties of a protein (a) always remain the same (b) are sometimes completely changed

142 PROTEINS

(c) are destroyed (d) are always completely changed

4. The pleated-sheet structure is (a) inflexible (b) right-handed (c) inelastic (d) arranged in a spiral

5. The overall shape of a protein chain is described by its (a) primary structure (b) secondary structure (c) tertiary structure (d) function

6. Hemoglobin consists of (a) a triple helix (b) four separate polypeptide chains (c) long, thin, rigid "cables" (d) three polypeptide chains held together by hydrogen bonds

7. An antibody is an example of a (a) transport protein (b) toxin (c) hormone (d) protec-tive protein

8. Complete hydrolysis of a protein produces (a) amino acids (b) peptides (c) water and carboxylic acid (d) ammonia and carbon dioxide

9. Denaturation involves (a) the breaking of the peptide bonds (b) destruction of the primary structure (c) the return of a protein to its native conformation (d) destruction of the secondary and tertiary structure

10. When a tooth decays it undergoes (a) fluoridation (b) defluoridation (c) calcification (d) decalcification

1. Bonded to the alpha-carbon of an amino acid are a "side-chain," a

hydrogen atom, an amino group, and a(n)

FILL-IN QUIZ

2. The charge of an amino acid depends on the of its solution.

3. Polypeptides are polymers of linked by peptide

bonds.


4. The alpha-helix and pleated-sheet secondary structures result from

bonding.

5. The structure of a protein is its complex,

3-dimensional conformation, resulting from the folding of the polypep-

tide chain.

6. , which is the most abundant protein in your

body, has a strong, rigid structure.

7. Hemoglobin is classified by shape and solubility as a

protein; by function it is a protein.

8. The most important reaction undergone by proteins is

9. A denatured protein is returned to its native conformation in a process

known as .

10. Bone consists of and .


1. 2. 3. 4. 5.

protein amino acid peptide bond polypeptide alpha-helix

6. disulfide bond 7. hydrophobic bond 8. salt bridge 9. denaturation

10. calcification

(a) a bond formed through the oxidation of the sulfhydryl groups of two cysteine side chains

(b) the chemical bond between the carboxylic acid group of one amino acid and the amino group of another amino acid

144 PROTEINS

(c) a process by which calcium is deposited in tooth and bone tissue (d) a bond formed by ionic attraction between positively charged groups

and negatively charged groups within a protein molecule (e) the clustering of nonpolar side chains of amino acids with each other to

form weak bonds (f) the destruction of the native conformation of a protein (g) complex molecule composed primarily of carbon, hydrogen, oxygen,

and nitrogen; the main source of nitrogen in the diet (h) a polymer of amino acids linked by peptide bonds (i) a molecule which contains both an amino group and a carboxylic acid

group as well as a "side chain," containing another group (j) the coiling of a polypeptide chain in a spiral arrangement, produced by

hydrogen bonding


Amino acids contain an amino group (—NH2) and a carboxylic acid group (—COOH). Both groups are usually attached to the same carbon atom (the alpha-carbon). Also bonded to the alpha-carbon are a hydrogen atom and a group ("side chain") which varies from one amino acid to another. (a) (b)

(c)

(a)

The chiral amino acids have the L configuration. When put in a neutral solution, the carboxylic acid end loses its proton and the amino group gains a proton. The doubly charged molecule, or zwitterion, remains neutral as a whole. Some amino acids are essential because they are needed for normal growth and maintenance of tissue, but they cannot be synthesized in the body. The essential amino acids are isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine (as well as histidine for children). A protein is a macromolecule which consists of very large, naturally-occurring polypeptides.

(b) Γ Οι Γ

4 - N H - C H -Π \ side chain

OT r

NH-CH-C

O-i NH-CH-C-hbackbone

I peptide bond

5.

(c) The "primary structure" shows the sequence of amino acids-exactly which are present and the order in which they are connected on the polypeptide chains.

The two main types of secondary structure are the alpha-helix and the pleated sheet (or beta-pleated sheet). The alpha-helix consists of the coiling of a polypep-tide chain in a spiral arrangement. If is both flexible and elastic. The pleated sheet has a sheetlike network in which there are folds or pleats. It is flexible but inelastic, (a) The tertiary structure is maintained by linkages which result from inter-

actions between amino acid side chains within the protein.

ANSWERS 145

(b) Unlike hydrophobic bonds, which are noncovalent, disulfide bonds are cova-lent, creating cross-links that firmly connect different regions of the protein chain.

6. (a) The basic unit of collagen is a triple helix (tropocollagen) made up of three polypeptide chains twisted around each other and held together by hydrogen bonds. The resulting cables, which are long, thin, and rigid, line up next to each other to form fibers, which are cross-linked for extra strength. This strong, rigid structure makes collagen an excellent component for supportive and connective tissue (skin and the organic part of bone),

(b) Hemoglobin is the oxygen carrier of the red blood cells. The heme group contains an iron ion that can bind a molecule of oxygen, carrying it from the lungs to the tissues.

7. (a) A globular protein has a ball-like shape and is soluble in water. (b) Contractile proteins stretch or contract as a muscle is relaxed or tensed.

Hormones regulate chemical processes in the body. Transport proteins carry small molecules through the blood stream.

0 0 0 0 II II II II

8. NH 2 - C H - C - N H - C H - C - O H + H 2 Ο -+ NH 2 - C H - C - O H + NH? - C H - C - O H I I I I

Η CH3 Η CH3

9. (a) The secondary and tertiary structure of the protein is disorganized, usually by the breaking of the weak noncovalent bonds between the polypeptide chains,

(b) Alcohol and iodine destroy bacteria by penetrating them and denaturing their protein molecules.

10. (a) Bones are made of collagen and a complex salt, hydroxyapatite. The collagen provides toughness and springiness, while the hydroxyapatite provides hard-ness and rigidity.

(b) Teeth are made of dentine and enamel. Both have a higher mineral content than bones and are thus harder.

(c) Teeth and bones are formed by calcification, in which calcium is deposited in tissues.


1. (c) 6. (b) 2. ( 0 7. (d) 3. (b) 8. (a) 4. (c) 9. (d) 5. (c) 10. (d)

FILL - IN QUIZ

1. carboxylic acid group (—COOH) 2. pH 3. amino acids 4. hydrogen 5. tertiary

6. collagen 7. globular; transport 8. hydrolysis 9. renaturation

10. collagen, hydroxyapatite

146 PROTEINS


1. (g) 2. (i) 3. (b) 4. (h) 5. 0)

6. (a) 7. (e) 8. (d) 9. (f)

10. (c)

Enzymes and digestion


1. Explain what an enzyme does and how it works. 2. Classify enzymes according to their function or substrate. 3. Describe the factors that affect enzyme activity. 4. Recognize different types of enzyme cofactors. 5. Compare different forms of enzyme inhibition and relate to the action

of sulfa drugs. 6. Describe the use of enzymes in medical diagnosis and therapy. 7. Explain the role of enzymes in nerve impulse conduction and trans-

mission. 8. Identify the role of enzymes in carbohydrate digestion. 9. Identify the role of enzymes in lipid digestion.

10. Identify the role of enzymes in protein digestion.

STUDY QUESTIONS

1. What does an enzyme do? How?

147

16

148 ENZYMES AND DIGESTION

2. What do the following types of enzymes catalyze: oxidoreductases, hydrolases, lyases, ligases?

3. What factors generally increase enzyme activity?

STUDY QUESTIONS 149

(a) How do competitive inhibitors, noncompetitive inhibitors, and irreversible inhibitors differ?

(b) How does a sulfa drug work?

Define cofactor, coenzyme, and metalloenzyme.


(b) How is L-asparaginase used in therapy?

7. What role do enzymes play in conducting and transmitting nerve impulses?

8. How do enzymes aid in digestion of starch?

6. (a) If someone has increased concentrations of creatine phosphokin-ase and glutamic oxaloacetic transaminase in the blood, what might have happened to the person?


9. How do enzymes aid in digestion of lipids?

10. How do enzymes digest protein?


1. The special region of an enzyme where the substrate molecule fits is called the (a) activation energy (b) substrate bond (c) active site (d) catalyst

2. Enzymes which catalyze the breaking or making of double bonds are called (a) transferases (b) ligases (c) isomerases (d) lyases

3. Which factor generally does not influence enzyme activity? (a) temperature (b) pressure (c) pH (d) concentration of substrate

4. Flavin adenine dinucleotide (FAD) is (a) an apoprotein (b) an inorganic activator (c) a coenzyme (d) a metalloenzyme


5. If the product of the last enzyme in a series of reactions acts as an inhibitor for the first enzyme so that the whole system "shuts down," the process is known as (a) feedback inhibition (b) irreversible inhibition (c) competitive inhibition (d) noncompetitive inhibition

6. If tissues are damaged, as in the heart or kidneys, tissue enzymes (a) appear in the blood (b) are inhibited (c) should be administered to the patient (d) will no longer be present in the blood or urine

7. The passage of impulses along a neuron takes place because of (a) neurotransmission (b) the neutralization of the cells (c) polarization of the cells (d) inhibition of acetylcholinesterase

8. Digestion of large carbohydrate molecules begins in (a) the large intestine (b) the mouth (c) the stomach (d) the small intestine

9. The major site of lipid digestion is (a) the large intestine (b) the mouth (c) the stomach (d) the small intestine

10. The major site of protein digestion is (a) the large intestine (b) the mouth (c) the stomach (d) the small intestine

FILL-IN QUIZ

1. The molecule that is changed by a chemical reaction catalyzed by an

enzyme is called the .

2. The substrate of urease is .

3. The optimum pH of most enzymes is around

4. A cofactor firmly bound to an apoprotein is known as a

5. inhibitors bind reversibly to an enzyme

at a place other than the active site.


6. The enzyme is used to control some

types of cancer.

7. The difference in concentration of sodium and potassium cations

creates a(n) across the membrane, giving

the inside a negative charge, compared to the outside.

8. In the first step of digestion, large starch molecules are broken down

into .

9. Lipids must be emulsified by before they can be

digested by enzymes.

10. The end products of protein digestion are .


*· e n z

ym e

7. coenzyme 2. substrate 8. 3-

a c t i v* s i te 9. antimetabolite

4. activation energy 10. feedback inhibition 5' c o f a c t or

11 . neurotransmitter 6. prosthetic group 12. digestion

(a) a substance that prevents or slows down the action of an enzyme (b) a substance that prevents the enzymes of bacteria from synthesizing an

essential molecule needed for survival or growth (c) the process by which the product of the last enzyme in a chain of

reactions acts as an inhibitor for the first enzyme (d) a protein which acts as a biological catalyst (e) an organic cofactor (f) the molecule that is changed by a chemical reaction catalyzed by an

enzyme (g) the amount of energy that molecules need in order that a chemical

reaction take place (h) a special region in the structure of an enzyme into which the substrate

molecule fits perfectly


(i) a cofactor that firmly binds to an enzyme (j) a substance required by some enzymes for their activity (k) a substance which transmits an electrical signal after it reaches the end

of a neuron (1) the process by which complex food molecules are broken down into

simpler molecules


1. An enzyme acts as a catalyst, increasing the rate at which vital chemical reactions take place in the body, without being used up itself. The enzyme has an active site where the molecule to be changed by a chemical reaction (the substrate molecule) fits perfectly. The functional groups of the enzyme act on the substrate to speed up the reaction. The product then leaves the enzyme, freeing it to bind another substrate molecule.

2. Oxidoreductases catalyze oxidation-reduction reactions, which involve the loss or gain of electrons. Hydrolases catalyze hydrolysis, the reaction of a substrate with water. Lyases catalyze the breaking (or making) of double bonds. Ligases catalyze the formation of a bond between a carbon atom and another atom—oxygen, sulfur, nitrogen, or a second carbon atom.

3. Enzyme activity is increased when the concentration of substrate molecules is increased (up to a certain point). A rise in temperature increases enzyme activity, with 98.6°C the optimum temperature for most enzymes. (Too much heat will denature enzymes.) A pH between 6 and 8 is best for most enzyme activity. (An exception is pepsin, the enzyme of the gastric juice in the stomach.)

4. A cofactor is an additional substance required by some enzymes for their activity. A coenzyme is an organic molecule that serves as a cofactor. Metalloenzymes contain an inorganic cofactor—a metal ion.

5. (a) Competitive inhibitors, molecules that have structures similar to the sub-strate, bind reversibly at the active site, preventing the enzyme from catalyz-ing the reaction involving the substrate molecule. Noncompetitive inhibitors bind reversibly at a place other than in the active site, changing the structure of the enzyme so that it cannot perform its function. Irreversible inhibitors permanently modify or destroy part of the enzyme structure, also decreasing its activity.

(b) Sulfa drugs are competitive inhibitors which bind to a key enzyme needed by bacteria to synthesize folic acid, a substance needed for their growth and reproduction.

6. (a) The person may have had a heart attack one to two days prior to the blood analysis.

(b) L-asparaginase is used to control some cancers, such as certain types of leukemia.

7. Through active transport, enzymes cause the sodium ion concentration in cells to be low and the potassium ion concentration to be high. This difference in concen-tration creates an electrical potential across the membrane, giving the inside a negative charge compared to the outside. The charge difference enables impulses to be conducted along the nerve cell (neuron). After the signal is carried across the gap

ANSWERS 155

between cells, an enzyme destroys the chemical substance that transmitted the signal (neurotransmitter).

8. Starting in the mouth, enzymes catalyze hydrolysis of the food molecules so that larger molecules such as starch are broken into smaller ones like glucose.

9. Starting in the small intestine, enzymes hydrolyze at least 50-75% of the dietary fat. The final products of lipid digestion are primarily free fatty acids (70%) and monoacylglycerols (monoglycerides, 25%).

10. Enzymes digest protein to a large degree in the stomach but mainly in the small intestine. Strong acids in the stomach denature the proteins, causing them to expose their peptide bonds. The end products of hydrolysis are amino acids, which are absorbed by the blood.


1. (c) 2. (d) 3. (b) 4. (c) 5. (a)

6. (a) 7. (c) 8. (b) 9. (d)

10. (d)

FILL-IN QUIZ

1. substrate 2. urea 3. 7 4. prosthetic group 5. noncompetitive

6. L-asparaginase 7. electrical potential 8. polysaccharides and maltose 9. bile

10. amino acids


1. (d) 2. (f) 3. (h) 4. (g) 5. 0) 6. (i)

7. 8, 9.

10. 11. 12.

(e) (a) (b) (c) (k) 0)

Energy and carbohydrate metabolism


1. Relate the metabolism of carbohydrates to chemical energy. 2. Identify the role of coenzymes in carbohydrate metabolism. 3. Relate the structure of ATP to its ability to store and transfer energy. 4. Describe the uses of energy from ATP in the body. 5. Outline the major changes in glycolysis. 6. Outline the major steps in the citric acid cycle. 7. Describe the function of the respiratory chain. 8. Write and explain an equation to represent the complete oxidation of

glucose. 9. Compare carbohydrate anabolism to the catabolic process.

10. Differentiate between glycogenesis, gluconeogenesis, glycolysis, and glycogenolysis.

11 . Relate the normal blood glucose level and glucose tolerance to disorden of carbohydrate metabolism.

STUDY QUESTIONS

1. What happens to carbohydrates when they are metabolized?

156

17

STUDY QUESTIONS 157

3. How does ATP store and transfer energy?

4. How is the energy from ATP used by the body?

2. What role do coenzymes play in carbohydrate metabolism?

158 ENERGY AND CARBOHYDRATE METABOLISM

6. What are the major steps in the citric acid cycle?

7. What is the function of the respiratory chain?

5. Describe which chemical reactions occur during glycolysis.

STUDY QUESTIONS 159

9. Are the steps in carbohydrate anabolism the reverse of the catabolic sequence? Explain.

10. Explain how the following processes differ: glycogenesis, gluconeo-genesis, glycolysis, glycogenosis.

8. Explain what happens when glucose is completely oxidized, and write an equation that shows this process.


11 . What results would you expect from administering a glucose tolerance test to a normal person, a diabetic person, and a hypoglycemic person?


1. In order for a more complex molecule like glucose to be synthesized from a simpler molecule, such as carbon dioxide (a) combustion must occur (b) energy is usually required (c) the simpler molecule must be metabolized to the more complex

molecule (d) energy must be given off

2. The final acceptor of electrons during electron transport is (a) NADH (b) FADH2 (c) 0 2 (d) FAD

3. ATP + H20 -> (a) ATP + energy (b) ADP + Pi + energy (c) H2P 04~ + Pi + energy (d) ATP + Pi + energy

4. An increased metabolic rate often results from (a) pregnancy (b) shock (c) malnutrition (d) hypothy-roidism

5. glucose + 2ADP + 2Pi-> (a) 2 lactic acid + 4ATP + H 2 0 (b) 2 pyruvic acid + 2ATP + H 2 0 (c) 2 lactic acid + 2ATP + H 2 0 (d) 2 pyruvic acid + 4ATP + H 2 0

FILL-IN QUIZ 161

6. In the citric acid cycle, citric acid is finally converted back into (a) oxaloacetic acid (b) coenzyme A (c) NAD (d) carbon dioxide

7. The cycle of aerobic catabolism can be summarized by the following equation: pyruvic acid + 2 y 02 + 15ADP + 15P{ -* (a) 3 lactic acid + 10ATP + 5 H20 (b) 3C02 + 15ATP+17H20 (c) 3C02 +5ADP + 3 H20 (d) NAD + 4 H2 0 + 3ATP

8. The end products of glucose metabolism are (a) oxygen, carbon, and energy (b) the starting materials for photosynthesis (c) the starting materials for the citric acid cycle (d) hydrogen, carbon, and energy

9. During carbohydrate anabolism, most of the steps in the pathway from pyruvic acid to glucose occur by reversal of the sequence in (a) the critic acid cycle (b) the respiratory chain (c) photosynthesis (d) glycolysis

10. The process of converting glycogen to glucose through the hydrolysis of the acetal linkages is (a) glycogenesis (b) glycolysis (c) gluconeogenesis (d) glycogenolysis

11 . If a glucose tolerance test shows an abnormally high level of glucose in the blood, the person is possibly (a) hypoglycemic (b) diabetic (c) anemic (d) normal, but obese

FILL-IN QUIZ

1. A process in which energy is given off is called ;

one in which energy is absorbed is called .

2. During electron transport, certain coenzymes serve as

3. In general, the formation of a phosphate bond

energy and its hydrolysis energy.



1. metabolism 2. electron transport 3 oxidative phosphorylation 4. energy coupling 5. catabolism 6. anabolism 7. basal metabolism

8. glycolysis 9. citric acid (Krebs) cycle

10. coenzyme A 11 . respiratory chain 12. gluconeogenesis 13. glycogenesis 14. glycogenolysis

4. The amount of heat you give off 12 to 15 hours after your last meal,

under resting conditions, is known as your

5. Glycolysis takes place in the absence of

6. is an aerobic process which takes place in the

presence of oxygen and releases more energy than does the anaerobic

process of glycolysis.

7. The products of aerobic catabolism are carbon dioxide, water, and

8. The end products of glucose metabolism are

and

9. The formation of new glucose from simpler molecules takes place in a

process called

10. The process by which glucose units are linked together to form glyco-

gen is called .

11 . ,— results when the glucose level drops below

normal.

ANSWERS 163

(a) the linking together of glucose units to form glycogen (b) the process by which electrons are transferred from one compound to

another until they reach oxygen (c) the breaking down of complex molecules into simpler ones, releasing

energy (d) a substance involved in the citric acid cycle (e) a series of aerobic reactions that produce ATP (0 the formation of new glucose in the body from simpler molecules (g) the process in which glycogen is converted back into glucose by

hydrolyzing the acetal linkages (h) the amount of heat you give off 12 to 15 hours after the last meal,

under resting conditions (i) the complex chemical steps by which your enzymes transfer matter and

energy from your surroundings to your body 0) the addition of H2P04"(Pi) to ADP to form ATP (k) the linking of an endergonic reaction with an exergonic reaction (1) the synthesis of large molecules needed by the cells, using the small

molecules and energy provided by catabolism (m) the breakdown of sugar in a series of anaerobic reactions (n) a series of enzymes which are involved in electron transfer coupled with

the synthesis of ATP


1. When metabolized, carbohydrates release the energy contained in their bonds in a series of chemical reactions as they are broken down into simpler molecules.

2. Coenzymes act as electron carriers in the oxidation process during which electrons are removed from the bonds of carbohydrate molecules and transferred to other compounds. Coenzymes can either accept or donate electrons.

3. Energy is stored in the bonds of ATP (adenosine triphosphate), which is formed from ADP (adenosine diphosphate) by the addition of Η2Ρ04~(Ρ|, inorganic phos-phate). The stored energy is released during hydrolysis by breaking the bond connecting the last phosphate. Thus ATP picks up energy given off during oxida-tion and transfers it to the processes in the cell that require work to be done.

4. The energy from ATP is used to carry out the reactions of anabolism, in which large molecules are synthesized from smaller ones. ATP energy is also used to do mechanical work, such as contracting muscles, and transport work, such as secreting urine or conducting nerve impulses. Excess energy is given off as heat.

5. During glycolysis, a 6-carbon glucose molecule is broken into two 3-carbon mole-cules of glyceraldehyde. This process uses up two molecules of ATP to make "high-energy" phosphate esters of the sugar molecules. Each glyceraldehyde is oxidized to an acid, giving two electrons to an NAD coenzyme. A phosphate bond is formed to store the large amount of energy thus released. This energy is used to convert ADP to ATP. Finally, pyruvic acid is reduced to lactic acid, oxidizing the NAD coenzyme back to its original form so that glycolysis can continue.


6. The citric acid (Krebs) cycle begins when the 2-carbon acetyl group from acetyl coenzyme A (acetyl Co A) joins with 4-carbon oxaloacetic acid to form 6-carbon citric acid. In a series of reactions, two carbon dioxide molecules are formed and other transformations occur, converting citric acid back into oxaloacetic acid.

7. The respiratory chain, which is a series of enzymes, transfers electrons to oxygen, a process which is coupled with the synthesis of ATP.

8. When glucose is completely oxidized, it is converted to C O 2 and H 20 , producing energy

glucose + 6 0 2 + 36ADP + 36 Pi 6C0 2 + 36ATP + 42H 20 9. No, the chemical pathways for carbohydrate anabolism are not simply the reverse

of the catabolic pathways. One difference is that the formation of glucose from simpler molecules (gluconeogenesis) requires the use of ATP and GTP molecules for energy.

10. In gjycogenesis, glucose units are linked together to form glycogen, the storage form of glucose. Iri gluconeogenesis, new glucose is formed from simple molecules, with the aid of ATP and GTP molecules. In glycolysis, which takes place in the absence of oxygen, a glucose molecule is broken into two lactic acid molecules, and two molecules of ATP are generated. In glycogenosis, glycogen is converted back into glucose through the hydrolysis of the acetal linkages.

11. In a normal person, you would expect the blood glucose to return to its original values by the end of the second hour because of increased glycolysis and glycogene-sis stimulated by the added glucose and resulting increase in insulin secretion. In a diabetic person, you would expect the already high blood sugar level to increase even further and to decline very slowly. You would expect a hypoglycemic individual to show an initial level which is low and which falls even further after the glucose has been administered because of insulin secretion.


1. (b) 7. (b) 2. (c) 8. (b) 3. (b) 9. (d) 4. (a) 10. (d) 5. (c) 11. (b) 6. (a)

FILL- IN QUIZ

1. exergonic, endergonic 2. electron carriers 3. requires, releases 4. basal metabolism 5. oxygen 6. respiration

7. ATP 8. carbon dioxide, water 9. gluconeogenesis

10. gly oogenesis 11. hypoglycemia

ANSWERS 165


1. (i) 8. (m) 2. (b) 9. (e) 3. 0) 10. (d) 4. (k) 11. (n) 5. (c) 12. (f) 6. (1) 13. (a) 7. (h) 14. (g)

Metabolism of lipids


1. Describe in words the fatty acid cycle. 2. Compare the products and energy yield of fatty acid and glucose

oxidation. 3. Contrast lipogenesis to the catabolic pathway. 4. Relate acetyl-CoA to both carbohydrate and lipid metabolism. 5. Explain the causes and symptoms of ketosis in starvation and diabetes

mellitus. 6. Describe the effect of ketoacidosis. 7. Discuss the function of depot lipid in relation to metabolism. 8. Explain the causes and consequences of obesity. 9. Relate blood lipids to atherosclerosis.

10. Describe the effect of the diet on blood lipid levels.

166

18

STUDY QUESTIONS 167

2. How much ATP is produced by the oxidation of fatty acids? Of glucose?

STUDY QUESTIONS

1. What are the major steps in the fatty acid cycle?

168 METABOLISM OF LIPIDS

4. Draw a diagram, showing the role acetyl Co A plays in carbohydrate and lipid metabolism.

3. How does lipogenesis differ from the fatty acid cycle?

STUDY QUESTIONS 169

(b) Why can starvation and diabetes mellitus cause ketosis?

6. What causes ketoacidosis and what are its symptoms?

5. (a) What are the symptoms of ketosis?


7. (a) How is depot lipid used by the body?

(b) Why is it important that the depot lipid is as saturated as possible (without becoming solid at room temperature)?

(c) Why are lipids a better storage form than glucose?

8. (a) What is the main cause of obesity?

(b) What medical problems is an obese person more likely to face than a person of normal body weight?

9. What causes atherosclerosis and why does it often result in hyperten-sion?


10. Why might a typical meat-eating American be more likely to develop heart disease than a strict vegetarian who eats only fruits, nuts, grains, and vegetables?


1. The acetyl CoA and reduced coenzymes produced by the fatty acid cycle can be channeled (a) into the citric acid cycle and the respiratory chain (b) only into the fatty acid cycle again (c) into the process of glycolysis (d) into the synthesis of amino acids

2. Compared with the oxidation of glucose, the oxidation of one fatty acid molecule produces (a) about the same amount of ATP (b) almost four times as many ATP molecules (c) over ten times as many ATP molecules (d) less than half as many ATP molecules

3. Which of the following is synthesized very differently from the others listed? (a) phospholipid (b) sphingolipid (c) cholesterol (d) triacylglycerol

4. Acetyl CoA plays a (a) minor role in lipid metabolism (b) minor role in carbohydrate metabolism


(c) major role in the metabolism of both lipids and carbohydrates (d) major role in lipid metabolism, but a minor role in carbohydrate

metabolism 5. Ketosis results from

(a) overproduction of acetyl CoA (b) underproduction of acetyl CoA (c) consumption of too much sugar (d) underproduction of ketone bodies

6. Ketoacidosis is caused by ketone bodies that are (a) more basic than the carbonic acid in the blood's buffer system (b) more acidic than the carbonic acid in the blood's buffer system (c) all carboxylic acids (d) neutral, thus neutralizing the blood, which is normally slightly

acidic 7. Lipids are stored mainly in the form of

(a) fatty acids (b) serum albumin (c) triacylglycerols (d) lipoproteins

8. The best way to lose weight is (a) cut down on calories (b) exercise before each meal (c) consume more calories between meals (d) drink at least eight glasses of water per day

9. Lipid deposits on the inner walls of the arteries of a person with atherosclerosis consist mainly of (a) triglyceride (b) phosphoglyceride (c) fatty acids (d) cholesterol

10. A person with a high cholesterol level should especially avoid eating (a) margarine (b) butter (c) peanuts (d) corn oil

FILL-IN QUIZ

1. Fatty acids are oxidized in the of the cells by a

series of reactions known as the fatty acid cycle.

2. The oxidation of a fatty acid molecule yields about

times the number molecules of ATP as the oxidation of a glucose

molecule.

3. Lipogenesis enables excess to be stored as fat.


4. If energy is not immediately needed from the citric acid cycle, acetyl

CoA can be used to make triacylgjycerols and .

5. Two causes of ketosis are and

6. Ketoacidosis the pH of blood.

7. When depot lipid is used by the body, it enters the blood stream as

, bound to a protein, .

8. A weight which is % more than normal can be a medical

danger.

9. Atherosclerosis can often lead to , which can be

detected by measuring the blood pressure.

10. Studies show that hyperlipemia and atherosclerosis may occur because

of too much lipid and not enough

lipid in the diet.


1. fatty acid cycle 2. lipogenesis 3. ketone bodies 4. ketosis

5. lipemia 6. ketoacidosis 7. obesity 8. atherosclerosis

(a) the anabolic pathway by which fatty acids and triacylglycerol are synthesized from glucose

(b) a catabolic sequence in which the long hydrocarbon chains of fatty acids are shortened two carbons at a time, producing acetyl CoA

(c) a condition resulting from overproduction of ketone bodies (d) acetoacetic acid, beta-hydroxybutyric acid, and acetone; three mole-


cules that can accumulate in the blood and which are formed from acetyl CoA

(e) a high concentration of lipids in the blood (f) a condition in which the inner layer of the artery walls is thickened by

lipid deposits made primarily of cholesterol (g) the condition of having a large excess of body fat (h) a decrease in the pH level of the blood caused by the overproduction of

ketone bodies


3.

In the fatty acid cycle, a fatty acid first is activated by forming a thioester with coenzyme A, using up a molecule of ATP. Two phosphate groups are lost from ATP in this reaction, leaving AMP (adenosine monophosphate) and liberating PPj (pyro-phosphate). Next, two hydrogen atoms are removed, forming the reduced coen-zyme, FADH 2, and leaving a double bond (enol) in the fatty acid. A reaction with water then occurs, creating an alcohol group that is oxidized to form a ketone functional group, reducing NAD

+ to NADH. Finally, a new CoA molecule enters

and causes cleavage to produce acetyl CoA and the CoA ester of the fatty acid now shortened by two carbon atoms. The fatty acid can run through the cycle again, losing again two carbon atoms and producing a molecule of acetyl CoA. The oxidation of one molecule of a typical fatty acid produces a total of 130 molecules of ATP, whereas glucose oxidation produces only 36 molecules of ATP for each molecule of glucose. The fatty acid "cycle" takes fatty acids apart two carbons at a time. In lipogenesis, fatty acids are synthesized by joining together two carbon units. This process takes place in the cell cytoplasm rather than the mitochondria and involves different reactions.

carbohydrates

citric acid cycle

lipids

fatty acid synthesis

(proteins)

cholesterol and ketone

body synthesis

5. (a) The symptoms of ketosis are an abnormally high concentration of ketone bodies in the blood (ketonemia) and urine (ketonuria) and the smell of acetone on the breath,

(b) Starvation and diabetes mellitus are similar in that both involve a "lack" of carbohydrates—in starvation because none are present, in diabetes mellitus

ANSWERS 175

because, although they are present, they cannot be used normally (due to a lack of insulin). In both situations, the body must use lipids for energy, in-increasing the production of acetyl CoA and consequently the formation of ketone bodies.

6. Ketoacidosis is caused by the buildup of two of the ketone bodies that are acidic (acetoacetic acid and beta-hydroxybutyric acid). They lower the pH of the blood and intensify the symptoms of ketosis: weariness, discomfort, loss of appetite, thirst, excessive urine secretion. Ketoacidosis also results in nausea, vomiting, dizziness, deep breathing, and coma.

7. (a) Depot lipid is used as a storehouse of energy that can be drawn on by the body when needed. It also acts as a "cushion" against physical blows to the body and as an insulator against loss of body heat.

(b) It is saturated (single bonds rather than double bonds) because more energy can thus be produced by oxidation.

(c) Lipid molecules provide more ATP during oxidation than does glucose. 8. (a) Overeating, consuming more calories than are needed by the body, is the

major cause of obesity, (b) An obese person is more likely to develop diabetes, gall bladder, liver, and

cardiovascular diseases. The person is also more likely to have complications when surgery is performed.

9. Atherosclerosis is caused by the thickening of the inner layer of the artery walls by lipid deposits (plaque) made largely of cholesterol. Because the arteries are clogged, the blood must be pumped harder to make it circulate, leading to high blood pressure (hypertension).

10. The typical American eats more animal (saturated) fats and thus has a higher level of blood lipids. The vegetarian eats vegetable and other unsaturated oils and thus has a low level of blood lipids. Although other factors are involved, it has been shown that a high lipid concentration in the blood is associated with the deposit of lipid plaques in the arteries.


1. (a) 6. (b) 2. (b) 7. (c) 3. (c) 8. (a) 4. •(c) 9. (d) 5. (a) 10. (b)

FILL- IN QUIZ

1. mitochondria 2. 4 3. glucose 4. fatty acids 5. starvation; diabetes mellitus

6. lowers.(decreases) 7. fatty acids; serum albumin 8. 10% 9. hypertension

10. saturated; unsaturated (or polyunsaturated)


KEY W O R D M A T C H I N G Q U I Z

1. (b) 5. (e) 2. (a) 6. (h) 3. (d) 7. (g) 4. (c) 8. (f)

Metabolism of proteins


1. Describe the events in the nitrogen cycle. 2. Relate amino acid catabolism to the citric acid cycle. 3. Outline the steps of the urea cycle. 4. Describe the anabolism of nonessential amino acids. 5. Discuss the catabolism of purines, pyrimidines, and heme. 6. Explain "nitrogen balance" in terms of the amino acid "pool." 7. Define the biological value of protein and relate this concept to the

diet. 8. Describe the consequences of protein deficiency. 9. Summarize the key aspects and relationships of carbohydrate, lipid, and

protein metabolism.

177

19

178 METABOLISM OF PROTEINS

2. (a) What is the function of transamination?

(b) In what forms do the amino acids enter the citric acid cycle?

STUDY QUESTIONS

1. Draw a diagram illustrating the nitrogen cycle.

STUDY QUESTIONS 179

(b) Where does the urea cycle take place?

4. Define nonessential amino acid and list three examples.

5. What are the end products of purine catabolism? Pyrimidine catabo-lism? Heme catabolism?

3. (a) Draw a diagram illustrating the urea (ornithine) cycle. (You do not have to give chemical formulas.)


6. (a) Where do the amino acids that make up the amino acid "pool" come from?

(b) How are the amino acids used?

7. (a) Define the biological value of a protein.

(b) Why does eating rice and beans together give them a greater biological value than if they were eaten at different times during the day?

8. List symptoms of protein deficiency.


9. Draw a diagram summarizing the major metabolic pathways.


1. The body digests nitrogen in the form of (a) N 2 (b) H N 03 (c) ammonia (d) amino acids

2. Amino acids that are transformed into one of the intermediates of the citric acid cycle are generally (a) glycogenic (b) ketogenic (c) ketoglutaric (d) acetic

3. How many ATP molecules are needed for the urea cycle? (a) 2 (b) 4 (c) 8 (d) 16

4. The main fate of amino acids is the synthesis of (a) alkaloids (b) coenzymes (c) hormones (d) protein

5. Gout results from the overproduction of , which is deposited in the cartilage. (a) stercobilin (b) urobilin (c) urea (d) uric acid


6. A negative nitrogen balance occurs during (a) infancy (b) childhood (c) pregnancy (d) old age

7. Which of the following has the greatest biological value? (a) corn (b) bread (c) milk (d) string beans

8. A victim of kwashiorkor has a diet lacking in (a) carbohydrates (b) lipids (c) protein (d) calories of any kind

9. Carbohydrate, lipid, and protein metabolism (a) operate independently of each other (b) are closely interconnected (c) produce products which cannot be used by each other (d) are independent of your diet

FILL-IN QUIZ

1. Most amino acids you eat end up in the where

they are metabolized and where many other important nitrogen com-

pounds are found.

2. Most amino acids entering the citric acid cycle enter as

3. In the urea cycle, each time one molecule of urea is excreted, two

molecules of are removed from the body.

4. is the raw material for making the nonessential

amino acids.

5. is catabolized to urobilin and stercobilin.

6. The excretion of serves as a "leveling device" to

maintain your nitrogen balance.

7. The biological value of a protein is the ratio of nitrogen

to the nitrogen by the body.

8. Protein deficiency can have serious consequences because of the short-

age of one or more

ANSWERS 183

9. The purposes of metabolism are to provide and

to supply for the synthesis of larger molecules.


1. nitrogen cycle 2. proteolysis 3. transamination 4. urea (ornithine) cycle

5. essential amino acid 6. nitrogen balance 7. biological value 8. kwashiorkor

(a) a process in amino acid catabolism in which the alpha-amino group is transferred to another molecule, usually alpha-ketoglutaric acid

(b) an amino acid that must be included in your diet because it cannot be synthesized by the body

(c) a disease caused by severe protein deficiency (d) a state in which the nitrogen ingested, mostly as amino acids, is equal to

the amount of nitrogen excreted, primarily as urea (e) a process in which nitrogen molecules are converted into nitrogen-con-

taining compounds that can be metabolized by plants and animals (f) a series of reactions in the liver that produce urea, the final end-product

of amino acid catabolism (g) a digestive process that breaks the peptide linkages of a protein,

producing free amino acids (h) the ratio of nitrogen retained to the nitrogen absorbed by the body


1.

anabolism animal catabolism protein

lightning bacteria

nitrogen wastes

nitrates (soil)

ammonia (soil)

bacteria 7


2. (a)

(b)

3. (a)

Through transamination, the amino groups of the different amino acids are transferred to glutamic acid, which can then be channeled into the final series of reactions that form the nitrogen-containing end products. Amino acids enter the citric acid cycle mostly as acetyl CoA, but also as alpha-ketoglutaric acid, succinic acid, fumaric acid, or oxaloacetic acid.

(^a^ha-amino groups)

glutamic acid

NH — CH— C—OH CH2

CH2

I HO—C=0 _ _Ë

aspartic acid

NH2—CH—C—OH I CH2

I HO—C=0

citrulline

NH-£-CH 2 o-CH—C—OH

NH

ornithine argmine

\ 0

X * II NH2-(- CH2- ) r CH—C—OH

NH NH-f-CH2-h-CH—C—OH

I NH,

Ο NH9—C—NH.

ANSWERS 185

(b) The urea cycle takes place in the liver. 4. A nonessential amino acid is one that can be synthesized by the body. Examples are

alanine, arginine, aspartic acid, cysteine, glutamic acid, glycine, proline, serine, tyrosine.

5. Purines are catabolized to uric acid. Pyrimidines are catabolized to ammonia and urea. Heme is catabolized to urobilin and stercobilin.

6. (a) The amino acids in the amino acid "pool" come from the diet, -from the synthesis of amino acids by the body, and from the breakdown ("turnover") of proteins.

(b) The amino acids are used to make new molecules or are broken down to urea, with the carbon skeleton entering the citric acid cycle.

7. (a) The biological value of a protein is the ratio of nitrogen retained to the nitrogen absorbed by the body. (A protein which lacks one of the essential amino acids will have no biological value compared to "complete" proteins.)

(b) Eating rice and beans together provides more biological value because amino acids cannot be stored. Rice contains more of the essential amino acid methionine, while the beans provide lysine.

8. Symptoms of protein deficiency are anemia, edema, peptic ulcers, low basal metabolism, growth failure, and diminished brain activity.

proteins amino acids

acetyl CoA ~ < — • fatty acids

steroids

ketone bodies

respira-respira-tory

chain H 20

energy (ATP)



1. (d) 6. (d) 2. (a) 7. (c) 3. (b) 8. (c) 4. (d) 9. (b) 5. (d)

FILL-IN QUIZ

1. 2. 3. 4. 5.

liver acetyl-CoA ammonia ammonia heme

6. urea 7. retained; absorbed 8. essential amino acids 9. energy; intermediates


1. (e) 2. (g) 3. (a) 4. (f)

5. (b) 6. (d) 7. (h) 8. (c)

Heredity and protein synthesis


1. Compare the structures of the nucleotides found in DNA and in RNA. 2. Describe the structure of the DNA molecule, including the nature of

the base pairing. 3. Explain the process of transcription. 4. Relate the role of transfer RNA to the process of translation. 5. Given the genetic code, write the polypeptide synthesized from a

specified portion of messenger RNA. 6. Describe the regulation of protein synthesis. 7. Explain the process of replication and its role in heredity. 8. Explain the causes and results of mutation. 9. Give examples of mutagens.

10. Describe the origin of molecular disease, with emphasis on sickle cell anemia and phenylketonuria.

11 . Explain the "central dogma" of molecular biology in terms of transfer of information.

STUDY QUESTIONS

1. (a) What are nucleosides? Nucleotides?

187

20

188 HEREDITY AND PROTEIN SYNTHESIS

(b) How do the nucleotides found in DNA differ structurally from those found in RNA?

2. (a) Describe the basic structure of DNA.

(b) How do the strands interact?

(c) If guanine appears on one strand, what must appear at the same spot on the other chain? Why?

3. (a) What happens during transcription?

(b) What function does transcription serve?

STUDY QUESTIONS 189

5. What amino acid sequence is formed by the following mRNA code: AAA/CCU/UUC/UAU/GAA/AGC?

6. How is protein synthesis regulated?

7. (a) How does a DNA molecule replicate?

4. What role does transfer RNA play in translation?


8. (a) How is a mutation caused?

(b) What is a frame-shift mutation and why is it usually lethal?

9. List three ways in which mutations are artificially caused.

10. (a) How does a DNA molecule in a person with sickle cell anemia differ from that in a normal person?

(b) What role does DNA replication play in heredity?


(b) What causes phenylketonuria (PKU) and how can it be controlled?

11 . Explain what is meant by the "central dogma" of molecule biology.


1. A nitrogen heterocycle attached to ribose is called a (a) base (b) nucleoside (c) nucleotide (d) deoxyribonu-cleic acid

2. If one strand of a DNA molecule has the sequence pTpCpGpA, the parallel strand must have the sequence (a) pTpCpGpA (b) pTpApGpC (c) pApCpGpT (d) pApGpCpT

3. Information on protein synthesis contained in the DNA code is carried to the cytoplasm by (a) triplets (b) mRNA (c) amino acids (d) DNA

4. Codons provide the code for synthesizing (a) proteins (b) DNA (c) tRNA (d) rRNA

5. CAC and CAU and mRNA codons for [refer to table of genetic code] (a) histidine (b) proline (c) leucine (d) glutamine

6. The repressor blocks protein synthesis by preventing production of (a) tRNA (b) mRNA (c) rRNA (d) DNA

7. Which step is not part of DNA replication? (a) separation of the double helix (b) formation of two double helixes, each with one strand from the

original helix and one new strand


(c) lining up of RNA nucleotides next to their complementary bases (d) base-pairing

8. Point mutations result in (a) the synthesis of a completely different protein (b) the change of one amino acid (c) the triplets after the mutation being read out of register (d) the addition or deletion of a nucleotide pair

9. Artificial mutations usually have results that are (a) beneficial (b) insignificant (c) harmful (d) not passed on to offspring

10. About how many molecular diseases exist? (a) 15 (b) 50 (c) 100 (d) 1,500

11 . Which sequence shows the "central dogma" of molecular biology? (a) DNA -> protein -* amino acids (b) RNA -» DNA-* protein (c) RNA -» protein -> DNA (d) DNA -* RNA protein

FILL-IN QUIZ

1. A nucleotide consists of a nucleoside with a

attached at the 5'-carbon.

2. In a DNA molecule, thymine can react only with

, guanine only with :

3. During transcription, the is copied into an RNA

molecule.

4. A tRNA molecule contains a group of three nucleotides called a

— that recognizes the appropriate codon on the

mRNA.

5. AAC and AAU are the mRNA codons for synthesizing

[Refer to table of genetic code.]

KEY WORD MATCHING QUIZ 193 ι

6. The group of genes whose activity is controlled together by the same

regulator is known as a(n)

7. Chromosomes are made up of , which consist of

8. A mutation consists of replacement of one pair

of complementary bases by another pair.

9. Certain dyes, such as the acridines, can cause mutations by slipping

between the of DNA.

10. About % of blacks in the United States have the sickle cell trait.

11 . Information travels from DNA to and then into a

sequence of .

LEY WORD MATCHING QUIZ

1. nucleoside 7. codon 2. nucleotide 8. replication 3. base-pairing 9. virus 4. genetic code 10. mutation 5. transcription 11 . mutagen 6. translation 12. molecular disease

(a) a special type of hydrogen bonding in which one nitrogen base can pair only with another specific nitrogen base

(b) the interpretation of the code from mRNA into the language of proteins (amino acids)

(c) the "messages" formed by groups of three bases in DNA which cor-respond to amino acids

(d) a hereditary condition that results from a mutation involving the formation of a specific defective protein

(e) a particle consisting of nucleic acid surrounded by a protein covering (f) the process by which a DNA molecule makes a copy of itself (g) a substance that causes mutation


(h) a group of three nucleotides which codes for a specific amino acid (i) a nucleic acid in which one of the nitrogen bases is attached to ribose (j) the process by which the DNA code is copied into an RNA molecule (k) a nucleoside with a phosphate group attached at the 5'-carbon; the

basic building block of the nucleic acid polymers (1) any change in the sequence of nucleotides in a DNA molecule


1. (a) A nucleoside is a ribose with a nitrogen heterocycle attached (at carbon-l'). A nucleotide, or nucleoside monophosphate, is a nucleoside with a phosphate group attached at the 5'-carbon. Nucleotides are the basic building blocks of the nucleic acid polymers,

(b) The nucleotides in DNA and RNA differ in that uracil is found in RNA instead of thymine as in DNA. Also, RNA contains ribose as the sugar component, while DNA is based on deoxyribose.

2. (a) DNA consists of two separate strands of nucleotides. The strands run parallel and wind around each other in the form of a right-handed helix. One strand runs in the opposite direction of the other.

(b) The strands interact through hydrogen bonding between parallel base pairs. (c) If guanine appears on one chain, cytosine must be on the other because

guanine and cytosine can interact only with each other .and not with adenine, thymine (or uracil).

3. (a) In transcription, the DNA code is copied into an RNA molecule. The DNA strands separate and the RNA nucleotides line up next to their complemen-tary bases on one of the strands of DNA and are attached to each other by an enzyme (RNA polymerase). The mRNA thus formed is an exact copy of the DNA except that it is a sort of "mirror-image" because it consists of the complementary bases rather than the same bases as the DNA strand,

(b) The mRNA formed by transcription acts as a messenger to carry the informa-tion for protein synthesis to the cytoplasm.

4. Transfer RNA has two main parts. One part "reads" the code of the mRNA. The other part attaches itself to a particular amino acid. Thus, there are at least 20 different kinds of tRNA, one to carry each of the amino acids. Each different tRNA contains an anti-codon which recognizes the appropriate codon (nucleotide triplet) on the mRNA.

5. lysine—proline—phenylalanine—tyrosine—glutamic acid—serine 6. Protein synthesis is regulated by repressor molecules that can bind at a control

point on the DNA and thus prevent formation of mRNA. When the repressor is inactivated, protein synthesis begins.

7. (a) A DNA molecule replicates by first separating. Deoxyribonucleotides attach themselves by base-pairing to the separated strands and are then linked together by an enzyme. The process results in two complete double helices, each identical to the original DNA molecule,

(b) DNA molecules make up the genes, which make up the chromosomes. It is the chromosomes that pass on hereditary traits.

8. (a) A mutation is caused by any change in the sequence of nucleotides in a DNA molecule.

ANSWERS 195

(b) A frame-shift mutation is one in which a nucleotide pair has been added or deleted. All the triplets after the mutation will be read out of register, resulting in the synthesis of a completely different protein.

9. Mutations can be caused by χ rays, gamma rays, ultraviolet radiation, alkylating agents, structural analogs, or dyes.

10. (a) A DNA molecule in a person with sickle cell anemia may contain a single substitution, such as adenine for thymine, in the portion that controls the synthesis of hemoglobin,

(b) Phenylketonuria (PKU) is caused by the lack of phenylalanine hydroxylase, the enzyme that converts phenylalanine to tyrosine. It can be controlled by restricting the intake of the amino acid phenylalanine in the diet of a growing child with PKU.

11. Information can be transferred from DNA to mRNA and then to a protein. DNA is the hereditary storage molecule that contains the genetic instructions. It is through replication that DNA transmits the code to other cells.


1. (b) 2. (d) 3. (b) 4. (a) 5. (a) 6. (b)

7. 8. 9.

10. 11.

(c) (b) (c) (d) (d)

FILL-IN QUIZ

1. phosphate group 2. adenine; cytosine

7. genes; DNA 8. point 9. base pairs

10. 10 11. mRNA; amino acids

3. DNA code 4. anti-codon 5. asparagine 6. operon


1. ( 0 2. (k) 3. (a) 4. (c) 5. ω 6. (b)

7. 8. 9.

10. 11. 12.

(h) (f) (e) (1) (g) (d)

Vitamins and hormones


1. Differentiate between the functions of food and vitamins in the body. 2. Identify the role, sources, and deficiency disease connected with thia-

min, riboflavin, niacin, folacin, pantothenic acid, vitamin B 6, vitamin B 1 2 , ascorbic acid, biotin, vitamin A, vitamin D, vitamin E, vitamin K.

3. Define recommended dietary allowance. 4. Describe the role of hormones in the body. 5. Identify the role, organ where found, and effect of excess and defi-

ciency of: thyroxine, parathormone, calcitonin, insulin, glucagon, testosterone, estrogen, progesterone, epinephrine, norepinephrine, Cor-tisol, aldosterone, vasopressin, adrenocorticotropin, gonadotropic hor-mones, thyrotropin.

6. Describe the role of the hypothalamic releasing factors in hormone regulation.

7. Explain the role of hormones in regulating (a) blood sugar level and (b) the menstrual cycle.

STUDY QUESTIONS

1. What is the function of vitamins and why are they needed in such small quantities?

196

21

STUDY QUESTIONS 197

2. Fill in the chart below.

Vitamin Function Deficiency

disease Sources

thiamin (Bx)

riboflavin (B2)

niacin (B 2, nicotinic acid)

folacin (folic acid, B 2)

panthothenic acid (B2)

B 6

B 1 2

ascorbic acid (C)

biotin (H)

A (retinol)

D (calciferol)

Å (tocopherol)

Ê (phylloquinone)

3. Define recommended dietary allowance.

198 VITAMINS AND HORMONES

(b) What role do hormones play in your body?

5. Fill in the chart below.

Hormone Location Effect Deficiency Excess

thyroxine

parathormone

calcitonin

insulin

glucagon

testosterone

estrogen

progesterone

epinephrine

norepinephrine

C o r t i s o l

aldosterone

—Continued

4. (a) Where are hormones produced?

STUDY QUESTIONS 199

Hormone Location Effect Deficiency Excess

vasopressin

oxytocin

adrenocortico tropin

follicle-stimulating hormone (FSH)

lutenizing hormone (LH) •

prolactin

chorionic gonadotropin

growth hormone (somatotropin)

thyrotropin

hypothalamic releasing factors

6. How is the release of hormones controlled?


7. How do hormones interact to keep the concentration of glucose in the blood fairly constant?

MULTIPLE-CHOICE AND MATCHING QUIZ

1. Which organ is especially sensitive to a vitamin deficiency? (a) skin (b) liver (c) heart (d) lungs

2. Match the following vitamins with the correct description.

1. thiamin (Bj) 2. riboflavin (B2) 3. niacin (nicotinic acid, B 2) 4. folacin (folic acid, B 2) 5. panthothenic acid (B 2) 6. vitamin B 6

7. vitamin B 1 2

8. ascorbic acid (C) 9. biotin(H)

10. vitamin A (retinol) 11 . vitamin D (calciferol) 12. vitamin Å (tocopherol) 13. vitamin Ê

(phylloquinone)

(a) deficiency results in a failure to make purines and thymine for DNA

(b) people unable to absorb this vitamin develop pernicious anemia (c) used to make coenzyme A; especially rich source is royal jelly

from bees (d) a coenzyme for carboxylase enzymes; found in chocolate, liver,

and other foods (e) deficiency results in beriberi (f) deficiency results in night blindness, xerophthalmia (g) deficiency causes pellagra (h) deficiency results in rickets (i) deficiency causes dermatitis of face and scrotum ("shark skin") (j) deficiency results in hemolysis of blood cells (k) found in fruits and vegetables; deficiency results in scurvy (1) involved in blood clotting (m) deficiency results in depression, confusion, and convulsions in

adults 3. The recommended dietary allowances may be inadequate for

(a) men over six feet tall (b) pregnant women (c) people who are sedentary (d) the middle-aged


4. Which statement about hormones is falsel (a) Hormones are all produced within the body. (b) Hormones control the synthesis of specific proteins (c) Hormones have long life spans (d) Hormones influence the rate of a reaction taking place in certain

cells. 5. Match the following hormones with the correct description.

1. thyroxine 9. epinephrine 2. parathormone 10. norepinephrine 3. calcitonin 11 . Cortisol 4. insulin 12. aldosterone 5. glucagon 13. vasopressin 6. testosterone 14. adrenocortico tropin 7. estrogen 15. gonadotropic hormones 8. progesterone 16. growth hormones

(a) used in birth control pills to prevent ovulation (b) the only molecule in the body that contains iodine (c) secreted in time of stress (d) deficiency results in low Ca

2+ level in blood

(e) deficiency results in high Ca2+ level in blood

(f) deficiency results in Addison's disease; found in the adrenal cortex (g) works in opposite direction from insulin; deficiency results in

hypoglycemia (h) female hormone responsible for secondary sex characteristics (i) conducts impulses at nerve ending; used to treat shock (j) deficiency results in diabetes mellitus (k) hemorrhage, dehydration, and excess salt intake cause its release (1) a male hormone (m) like Cortisol, oversecretion results in Cushing's syndrome (n) involved in estradiol and sex hormone production, milk secretion,

ovary development (o) keeps electrolyte balance of blood constant; excess results in

edema (p) excess leads to acromegaly (gigantism)

6. The release of hormones is regulated by (a) other hormones (b) the thyroid gland (c) the blood (d) the brain

7. The secretion of progesterone inhibits the release of prolactin and (a) follicle-stimulating hormone (b) luteinizing hormone (c) uterine mucosa (d) insulin


9. A lack of ascorbic acid results in .

10· is needed for carbohydrate, amino acid, and

fatty acid synthesis; its absence may cause dermatitis and weariness.

11 . Xerophthalmia, a major cause of blindness in young children in parts of

Asia, Africa, and Latin America, results from a lack of

12. Too much is toxic, causing loss of calcium from

bone, joint pains, and other symptoms.

13. Lack of vitamin Å shortens the life of cells.

14. Blood takes longer to clot in the absence of .

15. The describes the vita-

min requirements of almost everyone.

16. Hormones are produced by glands.

FILL-IN QUIZ

1. vitamins, which are stored in fat depots,

can build up to toxic concentrations.

2. A deficiency of thiamin may result in .

3. Riboflavin, found in organ meats, yeast, and wheat germ, can be

destroyed by and .

4. results from a niacin deficiency.

5. Drugs that interfere with folacin metabolism are used to control certain

types of .

6. Pantothenic acid is used by your body to make .

7. acts as an amino group carrier; a deficiency in

infants results in anemia, weight loss, and convulsions.

8. People who cannot absorb vitamin B 1 2 develop

FILL-IN QUIZ 203

21. works in the opposite direction of insulin; it is

secreted when the blood sugar level is low.

22. promotes and maintains the male sex organs and

secondary sex characteristics.

23. Secretion of produces female secondary sex

characteristics.

24. Progesterone prevents when given during the

fifth to twenty-fifth days of the menstrual cycle.

25. is the "fight or flight" hormone, secreted in

times of stress.

26. If not enough of the adrenal cortex hormones are produced,

develops.

27. Too little vasopressin results in the excretion of large quantities of

28. Adrenocorticotropin stimulates growth of the adrenal cortex and the

release of its steroid hormones and

29. stimulates the formation and secretion of mflk.

30. A deficiency of growth hormone results in .

31. Thyrotropin, which is involved with the thyroid gland, increases the

17. An overactive produces an excess of thyroxine.

18. The secretion of parathormone is inversely related to the level of

in the blood.

19. opposes the effects of parathormone, inhibiting

the loss of calcium from bone.

20. A low blood glucose level can result if a diabetic patient takes too much


rate of removal of from the blood by the thy-

roid.

32. The hypothalamic releasing factors act as a link between the hypo-

physis and the .

33. The menstrual cycle involves the periodic maturation of follicles of the

ovary accompanied by changes in the

membranes of the uterus.

4. recommended dietary allowance

(a) a biologically active organic substance needed in trace quantities for normal health and growth, but not manufactured by the body

(b) the amount of a vitamin considered adequate to meet the known nutritional needs of almost everyone

(c) a substance produced within the body that regulates various functions of the body

(d) a disease caused by the lack of a particular vitamin in the diet (e) special ductless organs that produce hormones (f) a condition that results if a diabetic takes too much insulin or fails to

eat enough food (g) synthetic compounds that stimulate protein synthesis


1. 2. 3.

hormone vitamin deficiency disease

5. endocrine glands 6. insulin shock 7. anabolic steroid


1. Vitamins are needed for normal health and growth. Because most vitamins serve as catalysts in the form of coenzymes, only small amounts are needed.

ANSWERS 205

2.

Vitamin Summary Chart

Name Function Deficiency

disease Sources thiamin

(B.)

riboflavin (B2)

niacin (B2, nicotinic acid)

folacin (folic acid, B2)

panthothenic acid (B2)

vitamin Be

vitamin B1:

ascorbic acid (vitamin C)

biotin (vitamin H)

vitamin A (retinol)

vitamin D (calciferol)

vitamin Ε (tocopherol)

vitamin Κ (phylloquinone)

decarboxylation (as pyrophos-phate)

dehydrogenation

beriberi

cheilosis, "shark skin"

dehydrogenation pellagra (as NAD and NADP)

one-carbon carrier (as tetrahydrofolate)

part of coenzyme A

amino carrier (as pyridoxal phosphate)

reduction, dehydration, transmethylation

oxidation-reduction, connective tissue

carboxylation

regenerates pigment for vision

calcium transport

inhibits oxidation of fatty acids, hematopoiesis

blood clotting

anemia, gastrointestinal changes

neuromotor disturbance

skin lesions,

pernicious anemia

scurvy

dermatitis

"night blind-ness," xeroph-thalmia

rickets

hemolysis of blood cells

loss of blood

seeds, pork, whole wheat bread

organ meats, yeast, wheat germ

meat, yeast, legumes

green leafy vegetables, liver

yeast, liver, eggs

liver, nuts, wheat germ

bacteria, organs

fruits, vege-tables

liver, yeast, grains

liver, fruits, vegetables

fish liver oil

plant oils

green leafy vegetables


3. Recommended dietary allowance refers to the amount of a vitamin considered adequate to meet the known nutritional needs of almost everyone.

4. (a) Hormones are produced in the body by the endocrine glands. (b) Hormones carry information from one organ to another. They serve as

regulators, integrating the various body functions to create a proper balance. Usually they exert their effect by controlling the synthesis of specific pro-teins.

5.

Hormone Summary Chart

Name Location Effect Deficiency Excess

thyroxine thyroid metabolic cretinism Grave's disease,

goiter

parathormone parathyroid calcium and

phosphate

metabolism

low C a 2+ level high C a 2+ level

calcitonin parathyroid,

thyroid

calcium and

phosphate

metabolism

high C a 2+ level low C a 2+ level

insulin pancreas blood

glucose

diabetes

mellitus

hypoglycemia

glucagon pancreas blood

glucose

hypoglycemia hyperglycemia

testosterone testes male sex

characteristics

eunuchoidism —

estrogen ovary female sex

characteristics

no sexual

development

—

progesterone ovary

(corpus

luteum)

uterine

mucosa

epinephrine adrenal pulse, blood slow response pheochromo-

medulla pressure cytoma (tumor) norepinephrine adrenal blood poor nerves pheochromo-

medulla pressure,

nerve con-

dition

cytoma (tumor)

ANSWERS 207

Name Location Effect Deficiency Excess

Cortisol adrenal glucose Addison's Cushing's

cortex metabolism disease syndrome aldosterone adrenal mineral dehydration edema

cortex balance

vasopressin. neuro- blood diabetes _ hypophysis pressure insipidus

oxytocin neuro- contraction — _ hypophysis of uterus

adrenocorticotropin adeno- adrenal Addison's Cushing's hypophysis hormone disease syndrome

stimulation

follicle- adeno- estradiol sterility _ stimulating hypophysis production

hormone (FSH)

luteinizing adeno- sex hormone sterility _ hormone (LH) hypophysis production

prolactin adeno- milk _ _ hypophysis secretion

chorionic placenta ovary — _ gonadotropin development

growth hormone adeno- growth of dwarfism acromegaly, (somatotropin) hypophysis bone/muscle gigantism

thyrotropin adeno- thyroid cretinism Grave's disease, hypophysis hormone goiter

formation

hypothalamic hypothalamus control of _ _ releasing adeno-

factors hypophysis


6. The release of hormones is controlled by other hormones, often of the hypothala-mus gland. These hypothalamic releasing factors serve as messengers to another gland (usually the hypophysis) and are controlled by the nervous system.

7. Insulin lowers the blood sugar level by promoting the use of glucose (through glycogenesis, glycolysis, and fat formation), while other hormones, like glucagon, produce glucose by glycogenolysis or gluconeogenesis.

MULTIPLE-CHOICE AND MATCHING QUIZ

1. (a) 2. 1. (e) 8. (k)

2. (i) 9. (d) 3. (g) 10. (0 4. (a) 11. (h) 5. (c) 12. (D 6. (m) 13. (1) 7. (b)

3. (b) 4. (c) 5. 1. (b) 9. (c)

2. (d) 10. (i) 3. (e) 11. (0 4. ω 12. (o) 5. (g) 13. (k) 6. (1) 14. (m) 7. (h) 15. (n) 8. (a) 16. (P)

6. (a) 7. (b)

FILL-IN QUIZ

1 lipid soluble 18. calcium 2. beriberi 19. calcitonin 3. sunlight; overcooking 20. insulin 4. pellagra 21. glucagon 5. leukemia 22. testosterone 6. coenzyme A (CoA) 23. estrogens 7. vitamin B 6 24. ovulation 8. pernicious anemia 25. epinephrine 9. scurvy 26. Addison's disease

10. biotin (vitamin H) 27. urine 11. vitamin A 28. Cortisol; aldosterone 12. vitamin D 29. prolactin 13. red blood 30. dwarfism 14. vitamin Κ 31. iodine 15. recommended dietary allowance 32. nervous system 16. endocrine 33. mucous 17. thyroid

ANSWERS 209


1. (c) 5. (e) 2. (a) 6. (f) 3. (d) 7. (g) 4. (b)

Chemistry of the body fluids


1. Describe the contents and role of blood plasma. 2. Explain the function of globulins as antibodies. 3. Relate blood components to the process of clotting. 4. Describe how the erythrocytes perform the transfer of gases in the

body. 5. Relate clinical conditions to the excess and deficiency of erythrocytes. 6. Define "blood group substances" and "Rh factors." 7. Discuss the role of leukocytes. 8. List the most important clinical blood tests. 9. Describe the role of interstitial fluid, lymph, saliva, and sweat.

10. State the composition of human milk. 11 . Describe the characteristics of urine. 12. State the components found in normal urine. 13. Describe the conditions that result in abnormal compounds in urine.

STUDY QUESTIONS

1. What are the components of plasma, and what functions does plasma serve?

210

22

STUDY QUESTIONS 211

3. Explain the roles played by fibrinogen, thrombin, and the platelets in blood clotting.

4. How are oxygen and carbon dioxide transported through the blood stream?

5. (a) Why might a person with polycythemia turn "blue?"

2. How do gamma globulins provide immunity against disease?

212 CHEMISTRY OF THE BODY FLUIDS

6. Compare the roles of "blood group substances" and "Rh factors" in the blood.

7. What role do leukocytes play in the body?

8. List the names of five important clinical blood tests.

(b) What is anemia?

STUDY QUESTIONS 213

(b) What roles do lymph, lymph nodes, and the entire lymphatic system play in the body?

(c) What are three functions performed by saliva?

(d) Why is sweat secreted?

What are the two main proteins in milk? The main carbohydrate? In what form are lipids present? What are four important organic con-stituents of milk?

(a) Where is interstitial fluid located and what function does it serve?


12. In urine, what are the major cations? The major anion? The major organic component?

13. (a) List three possible causes of glucosuria.

(b) What does the presence of blood or pus in the urine indicate?


1. The primary function of albumin in the blood plasma is (a) leukocyte transport (b) osmotic regulation (c) formation of antibodies (d) maintenance of pH level

2. Allergies, such as hay fever, result from (a) an abnormal immunity to a common substance (b) the absence of a specific antibody (c) the delayed reaction of a specific antibody (d) the absence of gamma globulins in the blood plasma

3. A lab technician may prevent a blood sample from clotting by adding a compound that prevents from entering the clotting process. (a) potassium citrate (b) vitamin Ê (c) sodium ion (d) calcium ion

4. The transport of oxygen and carbon dioxide is carried out by the (a) thrombocytes (b) leukocytes (c) erythrocytes (d) plasma

5. A person who cannot absorb vitamin B 1 2 from food might develop (a) aplastic anemia (b) pernicious anemia (c) hemolytic anemia (d) polycythemia vera

6. An Rh-negative mother giving birth to an Rh-positive baby forms (a) antibodies against the infant's erythrocytes

11 . What are the normal specific gravity and pH of urine?

FILL-IN QUIZ 215

(b) antigens against the infant's erythrocytes (c) antibodies against the "blood group substances" (d) antigens against the "blood group substances"

7. The formation of pus around a cut indicates (a) a leukocyte deficiency (b) the presence of leukocytes (c) an erythrocyte deficiency (d) the presence of erythrocytes

8. Which blood test might show kidney disease if the level is high and rickets if the level is low? (a) nonprotein nitrogen (b) total protein (c) inorganic phosphate (d) uric acid

9. Which fluid is involved in maintaining a heat balance in the body? (a) interstitial fluid (b) lymph (c) saliva (d) sweat

10. Human milk differs from cow's milk mainly in that it has (a) a higher protein content (b) a higher carbohydrate content (c) more iron (d) more vitamin A

11 . A person whose urine has an abnormally high specific gravity may be suffering from (a) diabetes mellitus (b) diabetes insipidus (c) hypertension (d) nephritis

12. A person with diabetes or muscular dystrophy may excrete more in the urine.

(a) urea (b) uric acid (c) creatine (d) creatinine 13. If a doctor suspects that a patient has a kidney disease, the doctor

should test for (a) glucosuria (b) pentosuria (c) proteinuria (d) bilirubin

that are only slightly soluble in water.

2. An antibody destroys or inactivates microorganisms and foreign protein

molecules, known as .

FILL-IN QUIZ

1. In the plasma, transports molecules in the blood

3. ., an insoluble polymer that forms the blood clot,

is formed from


7. , a form of cancer, is the uncontrolled production

of leukocytes.

8. The test might be used to check for gout or

leukemia.

9. The helps maintain the normal osmotic

balance between the blood and the tissues.

10. Because milk is low in , an infant whose diet is

only milk may develop .

11 . A , a chemical substance that increases the vol-

ume of urine excreted, is used to treat edema.

12. The concentration of , a waste product of purine

metabolism, in the urine is greater in people with gout.

13. Glycosuria is a condition in which there is an abnormally large amount

of present in the urine.

4. The conversion of hemoglobin to oxyhemoglobin takes place mainly in

the .

5. If a person loses blood, the body takes about days to

replace the plasma and days to return the erythrocyte

concentration to normal.

6. Both "blood group substances" and "Rh factors" act as

ANSWERS 217


1. intracellular fluid 8. interstitial fluid 2. extracellular fluid 9. diuretic 3. antibody 10. leukocyte 4. antigen 11 . erythrocyte 5. allergy 12. glycosuria 6. clotting 13. proteinuria 7. anemia

(a) an abnormal immunity to a common substance, such as plant pollen or animal hair

(b) the fluid which occupies the spaces between the cells in the body (c) fluid inside the cells (d) a chemical defense against loss of blood (e) a substance that destroys a specific antigen (f) fluid outside the cells (g) a foreign protein molecule, such as a toxin, which may trigger the

release of an antibody (h) a condition resulting from a deficiency of red blood cells (i) the presence of abnormally large amounts of protein in the urine 0') the presence of abnormally large amounts of sugar in the urine (k) a chemical substance that increases the volume of urine excreted (1) a red blood cell (m) a white blood cell


1. Blood plasma is made up of water, inorganic salts, proteins, including albumin, and organic compounds other than proteins. The plasma has suspended in it the cellular components of the blood, which bring oxygen and food molecules to the tissues and remove carbon dioxide and the waste products of metabolism. The albumin in the plasma regulates osmosis and transports, in the blood, molecules that are only slightly soluble in water.

2. Gamma globulins act as antibodies; they destroy or inactivate microorganisms and foreign protein molecules (antigens). Gamma globulins are specific—if one is formed in response to a particular antigen, it can react only with that antigen.

3. Fibrinogen is converted into fibrin, a fiberlike insoluble polymer that forms the blood clot. Thrombin is the enzyme that catalyzes this change. The platelets contain thromboplastin (necessary for the generation of thrombin) and other activating factors that are released when the platelet ruptures. The platelets also gather at the site of a wound, seal it, and act as a center around which the fibrin strands can form.


4. Oxygen is transported by binding to the iron of heme groups in hemoglobin. Carbon dioxide is transported as bicarbonate ion in the plasma or as carbamate groups on the hemoglobin chains.

5. (a) A person with polycythemia might develop a bluish-purple discoloration of the skin because of an increase in the blood volume and circulation time. This condition would lead to a larger amount of hemoglobin losing oxygen and becoming reduced to its blue form,

(b) Anemia is a condition that results from a deficiency of red blood cells. 6. Both "blood group substances" and "Rh factors" act as antigens. "Blood group

substances" react against the blood of another group, which releases antibodies against them. A person does not have antibodies against the Rh antigen, however, unless the body was previously exposed to blood containing it.

7. Leukocytes fight infection. They are carried to areas of inflammation where some of them surround and destroy bacteria and fragments of damaged tissue. Others form the plasma cells involved in making the antibodies that inactivate antigens-thus providing immunity against infection on a long-term basis.

8. Any five of the following are correct: albumin, bilirubin, cholesterol, creatinine, glucose, inorganic phosphate, nonprotein nitrogen (NPN), total protein, urea nitro-gen (BUN), uric acid.

9. (a) Interstitial fluid is located in the spaces between the cells. Most of it is in the form of a gel, which holds the cells together and enables substances to diffuse through it on their way between blood and tissue cells.

(b) Lymph absorbs fat from the intestine. The lymph nodes form certain types of white blood cells and act as filters, trapping dead cells and destroying bacteria. The lymphatic system returns such materials as protein and excess tissue fluid from the tissues to the blood and thus helps maintain the normal osmotic balance beween the blood and tissues.

(c) Saliva contains the enzyme alpha-amylase, which begins the hydrolysis of starch. It also contains mucus, which provides lubrication to aid swallowing, and it serves as a cleansing agent for food particles stuck in the teeth.

(d) Sweat is secreted to cool the body through evaporation. 10. Casein and beta-lactoglobulin are the two main proteins; lactose is the main

carbohydrate. Lipids are present as triacylglycerols. Calcium, phosphorus, potas-sium, sodium, magnesium, and chlorine are the major inorganic constituents.

11. The specific gravity of normal urine ranges from 1.005 to 1.030; the pH most commonly ranges from 5.5 to 6.5.

12. K+ and Na

+ are the major cations; CI" is the major anion. Urea is the main organic

part. 13. (a) Glucosuria may be caused by diabetes mellitus, anesthesia, asphyxia, emo-

tional states, and hyperthyroidism, (b) Blood indicates internal bleeding; pus indicates a kidney or urinary tract

infection.

MULTIPLE-CHOIC

1. (b) 5. 2. (a) 6 3. (d) 7, 4. (c) 8

QUIZ

(b) 9. (d) (a) 10. (b) (b) 11. (a) (c) 12. (c)

FILL- IN QUIZ

ANSWERS 219

1. albumin 2. antigens 3. fibrin; fibrin ogen 4. lungs 5. 1-3; 21-28 6. antigens 7. leukemia

8. uric acid 9. lymphatic system

10. iron; anemia 11. diuretic 12. uric acid 13. sugar


1. (c) 8. (b) 2. (f) 9. (k) 3. (e) 10. (m) 4. (g) 11 0) 5. (a) 12. 0) 6. (d) 13. (i) 7. (h)

Drugs and poisons


1. Define a drug and describe the events that occur after administration. 2. Describe the role of antibiotics and list two examples with their uses. 3. Describe the role of analgesics and list two examples with their uses. 4. Discuss the advantages and disadvantages of narcotic analgesics. 5. Identify the following types of anesthetics: (a) ethers, (b) halogenated

hydrocarbons, (c) gases, (d) intravenous, (e) local. 6. Describe the role of sedative-hypnotics and list two examples. 7. Describe the role of antianxiety and antipsychotic drugs and list two

examples. 8. Discuss the effects of alcohol on the body. 9. Describe the role of stimulants and list two examples.

10. Describe the effects of hallucinogens and give two examples. 11 . Describe the effect of drugs on the autonomic nervous system. 12. Describe the causes and effects of poisoning. 13. Discuss the different types of environmental pollutants and their

effects, including gases, particulates, heavy metals, pesticides, and car-cinogens.

STUDY QUESTIONS

1. (a) What is a drug?

220

23

STUDY QUESTIONS 221

2. (a) Why might a doctor prescribe an antibiotic?

(b) Which antibiotics are the most potent? What is their main disad-vantage?

(c) Which class of antibiotics is most widely used? What are two disadvantages of using them?

3. Why are analgesics administered? List two common analgesics.

(b) What happens after a drug is administered?

222 DRUGS AND POISONS

4. Give one advantage and one disadvantage of using a narcotic analgesic.

5. (a) List two anesthetic ethers.

(b) List two halogenated hydrocarbons used as anesthetics.

(c) List two gases used as anesthetics.

(d) List one intravenous anesthetic.

(e) List two local anesthetics.

6. (a) List three reasons why a sedative-hypnotic drug might be medi-

cally prescribed.

(b) Give the names of two commonly used barbiturates.

7. (a) Why might a doctor prescribe Equanil or Valium to relieve anxiety rather than a barbiturate?

STUDY QUESTIONS 223

8. What effects does chronic alcohol abuse have on the body?

9. (a) Why might a doctor prescribe a stimulant?

(b) List three examples of stimulants.

10. (a) What effects do hallucinogens have on the thought processes?

(b) List two hallucinogens.

(b) What effects might an antipsychotic drug have on a schizophrenic?


12. (a) How do poisons affect the body?

(b) What class of poisons accounts for the most deaths by poisoning in the U.S.?

13. What effects might high concentrations in the atmosphere of the following have on the body: ozone, sulfur oxides, asbestos fibers, mercury vapor, pesticides?

11 . How do sympathomimetic drugs differ from sympathoplegic drugs?



1. The guiding principle in prescribing drugs is that (a) it is best to try as many drugs as possible on a patient (b) the patient should not be harmed (c) every drug has very predictable effects (d) sex, age, and weight do not influence a drug's effect

2. Aplastic anemia, an often fatal blood disorder, is a possible side effect from taking (a) chloramphenicol (b) streptomycin (c) erythromycin (d) penicillin V

3. Aspirin does not act as (a) an antipyretic (b) an anti-inflammatory agent (c) an anti-biotic (d) a pain reliever

4. The most effective drug against severe pain is (a) codeine (b) opium (c) methadone (d) morphine

5. Halo thane is (a) a halogenated hydrocarbon (b) an intravenous anesthetic (c) a local anesthetic (d) an anesthetic ether

6. Barbiturates are divided into groups according to (a) how addictive they are (b) their effectiveness in relieving pain (c) how they are administered (d) the length of their effect

7. Which of the following is an antipsychotic drug? (a) Valium (b) Miltown (c> Thorazine (d) Equanil

8. Alcohol (a) depresses the central nervous system (b) stimulates the central nervous system (c) is most rapidly absorbed on a full stomach (d) causes water retention in the body

9. Amphetamines are medically prescribed to (a) stimulate the appetite (b) relieve anxiety (c) induce drowsiness (d) treat hyperactive children

10. Hallucinogens are prescribed by a doctor (a) to relieve anxiety (b) only rarely (c) as an anesthetic (d) to relieve depression

11 . Glaucoma is treated by (a) an adrenergic drug (b) an adrenergic blocking drug (c) a cholinergic drug (d) an anticholinergic drug


4. are medically prescribed only in cases of

severe pain and for limited periods of time.

5. Benzocaine and Novocain are examples of anes-

thetics.

6. Withdrawal from , which is more dangerous than

from narcotic analgesics, should be carried out in a hospital.

7. might be administered to reduce the

hallucinations of a schizophrenic patient.

8. It is illegal to drive with a blood alcohol concentration above %.

12. The attempt to chemically convert poisons into less toxic molecules takes place in the (a) liver (b) kidneys (c) blood (d) intestine

13. A person suffering from a chronic respiratory disease is especially endangered by high concentrations of (a) ozone (b) sulfur oxides (c) pesticides (d) mercury vapor

FILL-IN QUIZ

1. Drugs that can be bought without prescription are called

drugs; drugs can be

bought only with a prescription.

2. is often prescribed to patients who are allergic to

the penicillins.

3. In the digestive tract, aspirin is hydrolyzed to acetate and


9. is an alkaloid that acts as a stimulant and has

side effects similar to the amphetamines.

10. The most potent hallucinogen is

11 . drugs block some of the effects of

acetylcholine.

12. The are organs especially vulnerable to poisons.

13. Because it can gather in the skeleton like calcium,

is no longer a component of paints used inside houses.


1. drug 2. antibiotic 3. analgesic 4. drug-dependency 5. anesthetic

6. sedative-hypnotic drug 7. antipsychotic agent 8. stimulant 9. hallucinogenic agent

10. poison

(a) a drug that alters perceptions of space and time and which may cause hallucinations

(b) a drug that increases the activity of the central nervous system (c) a drug that relieves pain either by depressing the central nervous system

or by blocking the transmission of nerve impulses from the site of application

(d) a drug used to treat an infectious disease (e) a condition in which physiological disturbances will occur if the drug is

no longer administered (f) a chemical substance which causes injury or death (g) a drug that relieves pain (h) drugs, such as barbiturates, which are used to treat anxiety, hyperten-

sion, epilepsy, or insomnia (i) a drug that can alter mood and behavior as well as calm a mentally ill

person


(j) a chemical substance administered internally or applied externally to prevent or cure disease, treat symptoms, or for birth control or medical diagnosis


1. (a) A drug is a chemical substance that affects the body, usually by stimulating or depressing certain activities in the cell, replacing a deficient substance, killing or weakening a foreign organism, or causing irritation,

(b) A drug is absorbed into the blood and then distributed to various parts of the body, depending on the size and solubility of the drug molecules. It may undergo biotransformation. Finally it is excreted, usually into the urine.

2. (a) A doctor might prescribe an antibiotic to treat an infectious disease; the antibiotic kills or inhibits the growth of a microorganism that causes disease.

(b) Penicillins; they cause allergic reactions in about 5 to 10% of adults in the United States.

(c) Tetracyclines; they may cause gastrointestinal irritation and alteration of the normal microbial population of the intestine.

3. Analgesics are administered to relive pain. Aspirin; Darvon (propoxyphene). 4. One advantage is that they are the most powerful pain-relieving drugs available.

However, frequent use leads to a state of drug-dependency or addiction. 5. (a) diethyl ether; divinyl ether; fluoroxene; methoxyflurane

(b) chloroform; trichloroethylene; halo thane (c) cyclopropane; nitrous oxide (d) thiopental (pentothal); methohexital (Brevital) (e) procaine (Novocain); lidocaine (Xylocaine); benzocaine

6. (a) A sedative-hypnotic drug might be prescribed to treat anxiety, hypertension, epilepsy, or insomnia,

(b) phenobarbital; amobarbital; pentobarbital (Nembutal); secobarbital (Seconal); thiopental

7. (a) A doctor might prescribe these drugs because they are safer, less likely to be abused, and less likely to interfere with motor activities or to cause drowsiness.

(b) An antipsychotic drug might alter the schizophrenic's mood and behavior, reducing hallucinations and illusions.

8. Chronic alcohol abuse causes irreversible damage to the brain, nervous system, heart, and liver.

9. (a) A doctor might prescribe a stimulant to treat depression, curb the appetite in cases of obesity, improve performance, or calm hyperkinetic children,

(b) amphetamine; dextroamphetamine (Dexedrine); Benzedrine; methampheta-mine; cocaine, caffeine

10. (a) Hallucinogens affect mood, memory, and perception of space and time, without disturbing the central nervous system,

(b) lysergic acid diethylamide (LSD); marijuana; mescaline; psilocybin 11. Sympathomimetic (adrenergic) drugs produce effects similar to epinephrine or

norepinephrine. Thus, they are often prescribed to open the bronchial passages in a person with asthma. Sympathoplegic (adrenergic blocking) drugs block the effect of epinephrine and norepinephrine.

ANSWERS 229

12. (a) Poisons carried in the blood can destroy the tissues of an organ, inactivate enzymes, combine with cell components, or cause release of harmful sub-stances.

(b) medicine designed for internal use 13. Ozone can cause severe pulmonary edema. Sulfur oxides irritate the respiratory

system and can cause constriction of the air pathways. Asbestos fibers in the lungs can cause asbestosis, a respiratory disease, and lung cancer. Mercury vapor can lead to brain and central nervous system damage. Pesticides can cause tremors, convul-sions, and death.


1. (b) 8. (a) 2. (a) 9. (d) 3. (c) 10. (b) 4. (d) 11. (c) 5. (a) 12. (a) 6. (d) 13. (b) 7. (c)

FILL-IN QUIZ

1. proprietary; ethical 2. erythromycin 3. salicylate 4. narcotic analgesics 5. local 6. barbiturates 7. chlorpromazine (Thorazine)

8. 9.

1 (one) cocaine

10. lysergic acid diethylamide (LSD) 11. parasympatholytic (anticholinergic) 12. kidneys 13. lead


1. (J) 6. (h) 2. (d) 7. 0) 3. (g) 8. (b) 4. (e) 9. (a) 5. (c) 10. (f)

REVIEW QUESTIONS FOR APPENDIX

Basic mathematics for chemistry

To demonstrate an understanding of Appendix A, you should be able to:

1. Perform addition, subtraction, multiplication, and division of decimal numbers.

2. Express numbers in scientific notation and perform calculations. 3. Set up and solve proportions involving one unknown. 4. Use the unit-factor method to solve simple conversions.

1. Solve the following problems. (a) 0.35 + 3.5 + 35.0 = (b) 7 .59-1 .5 = (c) 4.31 X 0.112 = (d) 53.4 + 0.05 =

STUDY QUESTIONS

230

A

STUDY QUESTIONS

Solve the following problems. (a) Express 4,570; 45.7; and 0.457 in scientific notation. (b) (5 × 10

3) + (7 X 10

4) =

(c) (0.4 × 1 04) - (3 X 10

2) =

(d) (4X 1 03) X ( 2X 10

s) =

(e) (9 × 1 08) / ( 0 .3 X 10

4) =

231

2.

232 BASIC MATHEMATICS FOR CHEMISTRY

3. Solve the following problems by finding the value of X. (a) ± = J _

5 100

(b) 3 _ X 5 100

4. Using the unit-factor method, convert 12 feet to inches.


1. 0.021 X 0.03 = (a) 0.0063 (b) 0.00063 (c) 0.063 (d) 0.63

2. (4.1 Χ 103) + (3.2 X 10

2) =

(a) 7.3 Χ 103 (b) 7.3 X 10

s (c) 4.42 Χ 10

3

(d) 4.42 Χ 102

1 X 3. In the equation — = ,X is equal to

4 100 (a) 400 (b) 40 (c) 2.5 (d) 25

4. In three hours, there are (a) 180 min

2/sec (b) 30 minutes (c) 180 minutes

(d) 30min2/sec

ANSWERS 233

FILL-IN QUIZ

1. 0.15 ^0.5 = 2. (5.3 Χ ÉÏ

3) X (2 X 10"

5) =

3 In the equation = yjjjy, X is equal to

4. If there are four cups in one quart, five quarts equals.


1. (a)

(c)

0.35 3.5

35. 38.85

4.31 X 0.112

862 431

431 0.48272

(b)

(d)

7.59 -1.5

6.09

1068. 0.05,)53.4g

5 34 30 40 40

0 (a) (b) (c) (d) (e)

4.57 Χ 10 3; 4.57 Χ 10 1; 4.57 Χ 10"1

(0.5 Χ 104) + (7 X 104) = 7.5 X 104

(40 Χ 1 0 2) - ( 3 X 102) = 37 X 102 = 3.7 Χ 103

(4X 2)X 10<3 + 5> = 8X 108

(9 + 0.3) X 10<8 ~ 4> = 30 Χ 104 = 3.0 X 10s

3·

( a) i - m

SX= 100

loo

X = 20

4. inches = 124c€i X

( b ) ! = i w 5X = 300

õ _300 x " T "

X =60

12 inches

= 144 inches

. cups.


1. (b) 2. (c)

3. (d) 4. (c)

FILL-IN QUIZ

1. 0.3 2. 1.06 X 1 0 " 1

3. 4.

4 20


Metric system conversions

To demonstrate an understanding of Appendix B, you should be able to:

1. Convert units within the metric system. 2. Convert units between the English and metric system. 3. Convert between the Fahrenheit, Celsius, and Kelvin temperature

scales.

STUDY QUESTIONS

1. Using either the unit-factor method or the method of proportions, find the number of grams in 45 kilograms (kg).

234

B


2. If 1 inch (in.) equals 2.54 cm, how many cm are in 24 in.?

235

3. (a) Convert 40°C to the Fahrenheit scale.

(b) Convert 102°F to the Kelvin equivalent.


1. 250 ml equals (a) 0.25 liter (b) 0.025 liter (c) 2.5 liters (d) 25,000 liters

2. 50 grams equals pounds. (a) 1.1 (b) 11. 0 (c) 11 0 (d) 0.11

3. 32°C equals °F. (a) 0 (b) 57.6 (c) 89.6 (d) 75

236 METRIC CONVERSION SYSTEM

FILL-IN QUIZ

1. 0.08 gram equals milligrams.

2. There are cm in 3 inches.

3. 77°F equals °C.


t l k g _ 1000g

or

45 kg X

1 k g X Z = 45kgX 1000 g

v , 4 5 k g X 1000 g x Tki

X = 45,000 g

g = 45,000 g

2. cm = 244* Χ É ^ Ξ ί

= 61 cm

3. (a) °F= - | (40) + 32

_360 , ^ " — + 32

= 72 + 32 = 104°F

(b) ° C = | ( 1 0 2 - 3 2 )

= | ( 7 0 ) ^350

9

= 39°C

K= 39 + 273

K= 312

ANSWERS 237


1. (a) 3.(c) 2. (d)

FILL-IN QUIZ

1. 80 3. 25 2. 7.62


Orbitals

To demonstrate an understanding of Appendix C, you should be able to:

1. Write the electronic configurations of atoms up to atomic number 20. 2. Describe the single, double, and triple bond in terms of hybridization

and molecular orbitals.

STUDY QUESTIONS

1. Give the electron configurations for H, O, Al, C, N, and Ca.

238

C

ANSWERS 239

(b) What do double and triple bonds consist of?


1. Is2 2s

2 2p

5 is the electron configuration for

(a) sodium (b) fluorine (c) nitrogen (d) oxygen 2. A triple bond consists of

(a) 3 sigma bonds (b) 3 pi bonds (c) 2 sigma bonds and 1 pi bond (d) 2 pi bonds and 1 sigma bond

FILL-IN QUIZ

1. The electron configuration for lithium is

2. A bond is formed by the overlap of the ñ orbitals.


1. Η Is 1

Ο Is 2 2s22p4

Al Is 2 2s22p6 3s 23 p l

C Is 2 2s22p2

Ν Is 2 2s22p3

Ca Is 2 2s22p6 3s23p6 4s2

2. (a) A single bond is formed by the overlap of one sp orbital from each carbon atom (sigma bond).

2. (a) How is a single bond between two carbons formed?

240 ORBITALS

(b) A double bond consists of the sigma bond formed by overlap of the sp2

orbitals and the pi bond formed by overlap of the ρ orbitals. A triple bond consists of one sigma bond and two pi bonds.


1. (b) 2. (d)

FILL - IN QUIZ

1. Is 2 2s1

2. pi


Details of glucose catabolism

To demonstrate an understanding of Appendix D, you should be able to:

1. List the detailed steps of glycolysis. 2. List the detailed steps of the citric acid cycle.

STUDY QUESTIONS

1. Show, with equations, the ten steps of glycolysis.

241

D

242 DETAILS OF GLUCOSE CATABOLISM

2. Show, with equations, the seven steps of the citric acid cycle.

Question 1 (continued).

Question 2 (continued).

STUDY QUESTIONS 243


1. In the second step of glycolysis, glucose 6-phosphate is isomerized to (a) fructose 6-phosphate (b) fructose 1,6-diphosphate + ADP (c) dihydroxyacetone (d) glyceraldehyde 3-phosphate

2. In the final step of the citric acid cycle, malic acid is oxidized, producing (a) oxaloacetic acid + NAD

+

(b) oxaloacetic acid + NADH + H+

(c) fumaric acid + FADH2

(d) acetyl CoA + oxaloacetic acid

244 DETAILS OF GLUCOSE CATABOLISM

FILL-IN QUIZ

1. The final product of glycolysis is.

2. In the first step of the citric acid cycle, acetyl CoA and oxaloacetic acid

react to form and


1. (a) glucose + ATP hexokinase glucose 6-phosphate + ADP

(b) glucose 6-phosphate phoSphog]ucofeomerai fnictose 6-phosphate

(c) fructose 6-phosphate + ATP phosphofructokinasS fmctose 1,6-diphosphate + ADP

(d) (1) fructose 1,6-diphosphate aldolase dihydroxyacetone phosphate + glyceraldehyde 3-phosphate

(2) dihydroxyacetone phosphate t r i o se p h o s p h at e jsomerasS glyceraldehyde 3-phosphate

(e) 2glyceral<lehyde 3-phosphate + 2NAD* + 2P, 2(l,3-diphosphoglyeerie acid) + 2NADH + 2H

(f) 2(l,3-diphosphoglyeerie acid) + 2ADP phosphogiycerate kinase1

2(3-phosphoglyceric acid) + 2ATP

(g) 2(3-phosphoglyceric acid) phosphoglyceromuta^ 2(2-phosphogly eerie acid) (h) 2(2-phosphoglyeerie acid) enolase 2phosphoenolpyruvic acid + 2H 2 Ο

(i) 2phosphoenolypyruvic acid + 2ADP p y r u v a te k i n a 2pyruvic acid f 2ATP

(j) 2 pyruvic acid + 2NADH + 2H + dehydrogenase 2 1 a c t ic a c id + 2 N A D*

2. (a) acetyl CoA + oxaloacetic acid dtrate synthase c i t r ic + Co A (b) (1) critic acid aconitase cw-aconitic acid

(2) cw-aconitic acid isocitric acid

(c) isocitric acid + NAD + ^ t S 8 te dehydrogenase" alpha-ketoglutaric acid + C0 2

+ NADH

(d) (1) alpha-ketoglutaric acid + NAD + + GDP + Pi C o A. — — » succinic 1 succmyl thiokmase

acid + C0 2 + NADH + Η + GTP (2) GTP + ADP -GDP + ATP

(e) succinic acid + FAD succinate dehydrogenase fumaric acid + FADH2

ANSWERS 245

(f) fumaric acid + H 2 Ο f u m a r a^ malic acid

(g) malic acid + NAD* m a l a te dehydrogenase oxaloacetic acid + ΝADH + H +


1. (a) 2. (b)

FILL - IN QUIZ

1. lactic acid 2. citric acid; CoA


The cell

To demonstrate an understanding of Appendix E, you should be able to:

1. Describe the components of a cell.

MATCHING QUIZ

Match the following cell components with the correct definition.

1. cytoplasm 6. nucleus 2. endoplasmic reticulum 7. polysome 3. lysosome 8. Golgi complex 4. mitochondrion 9. cell membrane 5. nucleolus

location of aerobic process of respiration; contains many enzyme systems; center for ATP generation complex of mRNA and ribosomes involved in polypeptide synthesis part of cell containing chromosomes; site of DNA and RNA synthesis; surrounded by its own membrane involved in storage and modification of products of cell secretion involved in rRNA synthesis and ribosome formation; associated with chromosomes system of membrane-covered channels in the cytoplasm; passageway for internal transport; associated with ribosomes in protein synthesis surrounds cell, separating it from the environment aqueous phase in which the cell components are suspended; includes all of the cell except the nucleus contains digestive enzymes that break down ingested food

(a)

(b) (c)

(d) (e)

(f)

(g) (h)

(i)

246

E

ANSWERS 247


1. The part of a cell that contains the chromosome is the (a) polysomes (b) nucleolus (c) mitochondrion (d) nucleus

FILL-IN QUIZ

1. The aqueous phase in which the cell components are suspended is called

the ; it includes all of the cell except the

ANSWERS MATCHING QUIZ

1. (h) 6. (c) 2. (f) 7. (b) 3. (i) 8. (d) 4. (a) 9. (g) 5. (e)


1. (d)

FILL-IN QUIZ

1. cytoplasm; nucleus

GLOSSARY

Acid A substance that raises the hydrogen ion concentration of water Acidosis A condition in which the pH of the blood is lower than 7.35 Activation energy The amount of energy that molecules need in order for a chemical reaction to take place Active site A special region in the structure of an enzyme into which the substrate molecule fits perfectly and undergoes a chemical change Active transport An energy-requiring process that moves molecules across a membrane in the direction opposite to diffusion Adsorption The ability of a substance to hold other substances to its surface Alcohol A substance made up of molecules that contain a hydroxyl group connected to a hydrocarbon group Aldehyde A substance made up of molecules in which carbon is double-bonded to an oxygen atom and single-bonded to a hydrogen atom, leaving only one bond available for a hydrocarbon group Alkaloid A nitrogen-containing organic molecule of vegetable origin, usually with a heterocyclic ring system Alkalosis A condition in which the pH of the blood is greater than 7.45 Alkane An organic compound in which the number of hydrogen atoms is always two more than twice the number of carbon atoms; contains single bonds between carbon atoms Alkene A hydrocarbon that contains a double bond between two carbon atoms Alkyl group An "incomplete" molecule consisting of an alkane with one hydrogen atom removed Alkyl halide A molecule in which a halogen is substituted into an alkane Alkyne A hydrocarbon with a triple bond between two carbon atoms Allergy An abnormal reaction to a common substance, such as plant pollen or animal hair Alpha-helix The coiling of a polypeptide chain in a spiral arrangement, produced by hydrogen bonding Alpha radiation Particles that have two protons and two neutrons; helium nuclei Amide A product of the reaction of an amine with a carboxylic acid Amine A substituted ammonia molecule in which one or more hydrocarbon groups replace one or more hydrogen atoms Amino acid A molecule that contains both an amino group and a carboxylic acid group as well as a "side chain," containing another group Anabolic steroid A synthetic compound that stimulates protein synthesis

248

GLOSSARY 249

Anabolism The synthesis of large molecules needed by the cells, using the small mole-cules and energy provided by catabolism Analgesic A drug that relieves pain Anemia A condition resulting from a deficiency of red blood cells Anesthetic A drug that relieves pain either by depressing the central nervous system or by blocking the transmission of nerve impulses from the site of application Anion A negatively charged ion Antibiotic A drug used to treat an infectious disease Antibody A substance that destroys a specific antigen; part of the body's defense mechanism Antigen A foreign protein molecule, such as a toxin, that may trigger the release of an antibody Antimetabolite A substance that prevents the enzymes of bacteria from synthesizing a vital substance (metabolite) Antipsychotic agent A drug that can alter mood and behavior as well as calm a mentally i l l person Aromatic hydrocarbon A hydrocarbon, such as benzene, that has partial double-bond character in its ring structure Atherosclerosis A condition in which the inner layer of the artery walls is thickened by lipid deposits (plaque) made primarily of cholesterol Atom The basic building block of nature; consists of inner region, a nucleus, surrounded by electrons Atomic mass unit (amu) A unit of mass based on ^ t h the mass of a carbon atom in which one proton or one neutron has a mass of about 1 (amu) Atomic number A number equal to the number of protons in the nucleus of an atom; the most important identification of an atom Atomic weight The average of the atomic masses of the isotopes of an element as they are found in nature Avogadro's number 6.02 Χ 10 2 3; the number of particles in a mole Basal metabolism The amount of heat you give off 12 to 15 hours after the last meal, under resting conditions Base A substance that raises the hydroxide ion concentration of water Base-pairing A special type of hydrogen bonding in which one nitrogen base can pair only with another specific nitrogen base Beta radiation Electrons given off at high speed and energy Biological value The ratio of nitrogen retained to the nitrogen absorbed by the body Calcification A process by which calcium is deposited in tooth and bone tissue Carbohydrate An organic molecule containing carbon, hydrogen, and oxygen; a poly-hydroxyl ketone or aldehyde Carbonyl group A group made up of carbon double bonded to oxygen Carboxyl group A functional group formed by combining a carbonyl group and a hydroxyl group Carcinogenic Cancer producing

250 GLOSSARY

Catabolism The breaking down of complex molecules into simpler ones, releasing energy Catalyst A substance that increases a reaction rate but that can be recovered unchanged at the end of a reaction Cation A positively charged ion Cell membrane The part of a cell that separates it from the environment Chemical equation A "shorthand" way of describing the changes that occur in a chemical reaction Chemical reaction A process by which substances undergo chemical changes, forming new substances with different arrangements of atoms Citric acid (Krebs) cycle A series of reactions in which two-carbon fragments are oxidized, producing ATP in the presence of oxygen Clotting A chemical defense against loss of blood Codon A group of three nucleotides that code for a specific amino acid Coenzyme An organic cofactor Coenzyme A A substance involved in the citric acid cycle; carrier of the two-carbon acetyl group Cofactor A substance required by some enzymes for their activity Colloid A mixture in which one substance is dispersed in another; contains particles larger than those in a solution Compound A substance that consists of units formed by two or more atoms joined through chemical bonding Covalent bond A bond formed by the sharing of electrons between the nuclei of two atoms Crosslink A chemical bond between the chains of a polymer Cycloalkane An alkane that has a ring structure Cytoplasm The aqueous phase in which the cell components are suspended; includes all of the cell except the nucleus Deficiency disease A disease caused by the lack of a particular vitamin in the diet Denaturation The destruction of the native conformation of a protein structure Density The ratio of the mass of an object to its volume Depot lipid The fat stored in the body, primarily as triacylglycerols Detergent A synthetic molecule containing a polar end and a nonpolar end; suspends lipids in water Dialysis The diffusion of small molecules or ions across a dialyzing membrane in the direction of the less concentrated solution Diffusion The spreading out of a substance to fi l l a volume Digestion The process by which complex food molecules are broken down into simpler molecules by hydrolysis reactions Disaccharide A molecule formed from two monosaccharides joined by a chemical bond Dissociation (ionization) The separation of a compound into ions Disulfide bond A covalent bond formed through the oxidation of two sulfhydryl groups, such as in two cysteine side chains Diuretic A chemical substance that increases the volume of urine excreted

GLOSSARY 251

Drug A chemical substance administered internally or applied externally to prevent or cure disease, treat symptoms, or for birth control or medical diagnosis Drug-dependency A condition in which physiological disturbances will occur if the drug is no longer administered Electrolyte A substance that produces ions when it dissolves in water Electron A negatively charged subatomic particle found in shells that surround the nucleus of an atom Electron transport The process by which electrons are transferred from one compound to another Electronegativity The attraction of an atom for the electrons in a chemical bond Element A large collection of atoms that have the same atomic number; 106 known at present time Endocrine glands The special ductless organs that produce hormones Endoplasmic reticulum A system of membrane-covered channels in the cytoplasm; passageway for internal transport; associated with ribosomes in protein synthesis Energy coupling The Unking of an endergonic reaction with an exergonic reaction Energy level (shell) A definite region surrounding the nucleus where electrons are most likely to be found Enzyme A protein which acts as a biological catalyst Equilibrium A state of balance in which two opposing processes take place at the same rate Equivalent weight The weight in grams that will provide one mole of hydrogen ions (for an acid) or hydroxide ions (for a base) Erythrocyte A red blood cell Essential amino acid An acid that must be included in your diet because it cannot be synthesized by the body Ester The product of the reaction of a carboxylic acid with an alcohol Esterification The synthesis of an ester Ether A substance made up of molecules that contain an oxygen atom covalently bound to two hydrocarbon groups Evaporation The escape of molecules from the surface of a liquid to become the gaseous form of the liquid (vapor) Extracellular fluid The fluid outside the cells Fat An ester formed from fatty acids and glycerol; triacylglycerol (triglyceride) Fatty acid A molecule consisting of a 12 to 20 carbon atom chain with a carboxylic acid group at one end Fatty acid "cycle" A catabolic sequence in which the long hydrocarbon chains of fatty acids are shortened two carbons at a time, producing acetyl CoA Feedback inhibition The process by which the product of the last enzyme in a chain of reactions acts as an inhibitor for the first enzyme Fermentation The decomposition of a carbohydrate by the enzymes of a living organism Formula A "shorthand" way of expressing the numbers and kinds of atoms in a molecule Formula unit The smallest part of an ionic compound that still has the properties of that compound

252 GLOSSARY

Functional group An arrangement of atoms that cannot stand alone, but that controls the properties of the molecule in which it is located Gamma radiation Rays with extremely high energy and penetrating ability Gas The state of matter with no definite volume or shape, which expands without limit to fi l l the space it is in Genetic code The "messages" formed by groups of three bases in DNA, each cor-responding to one amino acid Gluconeogenesis The formation of new glucose in the body from simpler molecules Glycogenesis The linking together of glucose units to form glycogen Glycogenolysis The process in which glycogen is converted back into glucose by hy-drolyzing the acetal linkages Glycolipid A sphingolipid that contains a carbohydrate attached to a sphingosine Glycolysis The breakdown of sugar in a series of reactions, forming ATP in the absence of oxygen Glycoside A compound formed by the reaction of a monosaccharide at the hemiacetal group Glycosuria The presence of abnormally large amounts of sugar in the urine Golgi complex The part of a cell involved in storage and modification of products of cell secretion Half-life The time required for the decay of one-half of a given number of radioactive nuclei Half-thickness The thickness in millimeters needed to absorb one-half the emitted radiation Hallucinogenic agent A drug that alters perceptions of space and time and that may cause hallucinations Heat capacity The quantity of heat needed to increase the temperature of 1 gram of a substance by 1°C.

Hemiacetal A compound formed by the addition of an alcohol to an aldehyde group Heterocycle A ring compound containing two or more different kinds of atoms Hormone A substance produced within the body that regulates various functions of the body Hydrate A compound that contains a definite proportion of water molecules acting as single units Hydrocarbon A compound composed of carbon and hydrogen atoms only Hydrocolloid A polysaccharide that forms a colloid when dispersed in water Hydrogen bonding The attraction between the partially negative oxygen (or nitrogen) atom of one molecule and the partially positive hydrogen atom of another molecule Hydrolysis A chemical reaction in which water is added in the presence of a catalyst, causing a bond to break; also, the reaction of a salt with water, changing the pH from the neutral value Hydrophobic bond The clustering of nonpolar groups with each other to form weak bonds Hyperbaric therapy A form of oxygen therapy in which oxygen is administered at pressures greater than atmospheric pressure Indicator A dye whose color can be used to measure the pH of a solution

GLOSSARY 253

Inhibitor A substance that prevents or slows down the action of an enzyme Inorganic chemistry The study of compounds that do not contain carbon Insulin shock A condition that results if a diabetic takes too much insulin or fails to eat enough food Interstitial fluid The fluid that occupies the spaces between the cells in the body Intracellular fluid The fluid inside the cells Ion An electrically charged atom that has either gained or lost one or more electrons Ionic bond A bond formed by the attraction between oppositely charged ions; results from the transfer of electrons Isomer A molecule that has the same molecular formula as another molecule, but that has a different structure Isotonic Having the same osmotic pressure as another solution Isotope An atom related to another atom by having the same atomic number, but that has a different mass number Ketoacidosis A decrease in the pH level of the blood caused by the overproduction of ketone bodies Ketone A substance made up of molecules in which carbon is double bonded to an oxygen atom and in which two hydrocarbon groups are attached on either side of the carbonyl group Ketone bodies Acetoacetic acid, beta-hydroxybutyric acid, and acetone; three mole-cules that can accumulate in the blood and which are formed from acetyl CoA Ketosis A condition resulting from overproduction of ketone bodies Kinetic molecular theory The theory that describes molecules of a gas as constantly moving in a random way at very high speeds, often colliding with each other and the walls of their container Kwashiorkor A disease caused by severe protein deficiency Law of conservation of mass A law that states that matter is neither created nor destroyed during a chemical reaction Leukocyte A white blood cell Lipemia A high concentration of lipids in the blood Lipid An organic compound found in plants or animals that dissolves in nonpolar solvents, usually a triacylglycerol Lipogenesis The anabolic pathway by which fatty acids and triacylglycerols are synthe-sized from glucose Liquid The state of matter with a definite volume but no definite shape Lysosome The part of a cell that contains digestive enzymes that break down ingested food Mass The amount of matter a substance contains Mass number The total of protons and neutrons in the nucleus of an atom Matter The "stuff" all around you; anything that takes up space Meniscus The curved surface of a liquid caused by unequal forces of attraction by the container for the molecules of the liquid and attraction of the molecules of the liquid for each other Metabolism The complex chemical steps by which your enzymes transfer matter and energy from your surroundings to your body

Metal The category into which most elements fall; a substance which is shiny in appearance and which conducts heat and electricity well Mitochondrion The location in the cell of aerobic process of respiration; contains many enzyme systems; center for ATP generation Mixture A combination of two or more substances whose atoms have not been joined by chemical bonding Molarity A way of expressing concentration as the number of moles of solute per liter of solution Mole A unit that contains 6.02 Χ 1023 particles; a unit whose weight in grams is equal to the atomic, molecular, or formula weight of the substance Molecular disease A hereditary condition that results from a specific defective protein Molecular (formula) weight The sum of the atomic weights of all the atoms (or ions) present in the molecule (or formula unit) Molecule The unit formed by the covalent bonding of two or more atoms Monosaccharide The simplest carbohydrate unit Mutagen A substance that causes mutation Mutarotation The conversion between the alpha and beta forms of a monosaccharide Mutation A change in the sequence of nucleotides in a DNA molecule Nebulization The formation of a suspension of very fine particles in a gas Neurotransmitter A chemical substance that transmits an electrical signal after it reaches the end of a neuron Neutralization The reaction of an acid with a base Neutron A subatomic particle with no charge, found in the nucleus of an atom Nitrogen balance A state in which the nitrogen ingested, mostly as amino acids, is equal to the amount of nitrogen excreted, primarily as urea Nitrogen cycle A process in which nitrogen molecules are converted into nitrogen-containing compounds that can be metabolized by plants and animals Nonmetal A substance which is dull in appearance and which conducts heat and electricity poorly Nonpolar Equal sharing of electrons Normality A way of expressing concentration as the number of equivalents in one liter of solution Nuclear reaction A process in which the protons and neutrons of atoms are rearranged Nucleolus The part of the cell involved in rRNA synthesis and ribosome formation; associated with chromosomes Nucleoside A molecule that contains one of the nitrogen bases attached to a ribose Nucleotide A nucleoside with a phosphate group attached at the 5'-carbon; the basic building block of the nucleic acid polymers Nucleus The part of a cell containing chromosomes; site of DNA and RNA synthesis; surrounded by its own membrane Nucleus The central core of an atom, which contains protons and neutrons Obesity The condition of having a large excess of body fat Oil A vegetable fat, generally a liquid Optical isomers Molecules that are mirror images of each other, cannot be superimposed

252 GLOSSARY

GLOSSARY 255

Organic chemistry The study of compounds of carbon Osmosis The diffusion of solvent molecules through a semipermeable membrane in the direction of the more concentrated solution Oxidation The loss of electrons Oxidative phosphorylation The addition of H 2P0 4" (Pj) to ADP to form ATP, the energy being provided by oxidation Oxidizing agent A substance which accepts electrons during a chemical reaction Partial pressure The pressure exerted by one gas in a mixture of gases Peptide bond The chemical bond between the carboxylic acid group of one amino acid and the amino group of another amino acid, an amide linkage Periodic law The properties of the elements repeat in a regular way when the elements are arranged by their atomic number Phospholipid A substance differing from a triacylglycerol in that one of the hydroxyl groups is esterified with phosphoric acid instead of a fatty acid Plastic A material based on an organic substance of high molecular weight that is solid in its final form but has been shaped by flow at some stage in its manufacture Poison A chemical substance that causes injury or death Polar Unequal sharing of electrons Polymer A large molecule made by the linking together chemically of many small molecules Polypeptide A polymer of amino acids linked by peptide bonds Polysaccharide A large carbohydrate polymer Polysome The part of the cell consisting of a complex of mRNA and ribosome, involved in polypeptide synthesis Pressure The force applied to a certain area Prostaglandin A fatty acid containing 20 carbon atoms, with a cyclic structure in part of the molecule Prosthetic group A cofactor that binds firmly to a protein Protein A naturally occurring macromolecule composed primarily of carbon, hydrogen, oxygen, and nitrogen; the main source of nitrogen in the diet; consists of one or more polypeptide chains Proteinuria The presence of abnormally large amounts of protein in the urine Proteolysis A digestive process that breaks the peptide linkages of a protein, producing free amino acids Proton A positively charged subatomic particle found in the nucleus of an atom Quaternary ammonium salt A compound in which a nitrogen atom is bonded to four carbon atoms Radiation Particles or energy given off by the nucleus of an unstable atom Radioactivity The process of nuclear decomposition in which particles or energy are given off Radioisotope A radioactive isotope Recommended dietary allowance The amount of a vitamin considered adequate to meet the known nutritional needs of almost everyone Reducing agent A substance that donates electrons during a chemical reaction

256 GLOSSARY

Reducing sugar A carbohydrate that is readily oxidized because it contains a reactive aldehyde (or ketone) group Reduction The gaining of one or more electrons Replication The process by which a DNA molecule makes a copy of itself Respiration The exchange of gases within your body and between your body and the air so that oxygen is delivered to the tissues and carbon dioxide is removed Respiratory chain A series of enzymes that are involved in electron transfer coupled with the synthesis of ATP Salt An ionic compound that results from the chemical reaction of an acid with a base Salt bridge A bond formed by ionic attraction between positively charged groups and negatively charged groups within a protein molecule Saponification A reaction in which a strong base and an ester react to form a salt and an alcohol Saturated (a) In a molecule-made up of single bonds; (b) in a solution—containing as much solute as possible at a given temperature Scientific method An approach in which a hypothesis is proposed to explain certain observations and then tested by further observation and experimentation Sedative-hypnotic drug A compound such as a barbiturate, which is used to treat anxiety, hypertension, epilepsy, or insomnia Soap The product of the reaction of a fatty acid with a strong base; the salt of the fatty acid Solid The state of matter, with a definite volume and usually a rigid shape Solubility The amount of solute that can be dissolved in a certain amount of solvent at a particular temperature Solute The substance being mixed or dissolved in a solution Solution A homogeneous mixture of two or more substances Solvent The substance that does the dissolving in a solution Specific gravity The mass of a substance compared to the mass of the same volume of water (at a certain temperature); a measure that has the same numerical value as density but no units Sphingolipid A lipid that is based on the amino alcohol sphingosine Steroid A lipid that is not an ester, but that consists of molecules built around a framework of four saturated hydrocarbon rings fused together Stimulant A drug that increases the activity of the central nervous system Structural formula A "diagram" showing how the atoms are arranged in a molecule Substrate The molecule that is changed by a chemical reaction catalyzed by an enzyme Sulfhydryl group A functional group with the formula — SH Surface tension The unbalanced force at the surface of a liquid caused by the attraction of the molecules below the surface for the molecules at the surface of the liquid Surfactant A substance that lowers the surface tension of water by reducing the cohesive force between water molecules; "surface-active agent" Suspension A mixture whose particles are large enough to be seen with the naked eye, settles with time Teletherapy The irradiation of a cancer site with X rays or with gamma rays from an external source, such as one containing cobalt-60

GLOSSARY 257

Temperature A measure of how "hot" or "cold" a substance is Titration A procedure in which a solution of known base or acid concentration is slowly added to an acid or base until it is neutralized Transamination A process in amino acid catabolism in which the alpha-amino group is transferred to another molecule, usually alpha-ketoglutaric acid Transcription The process by which the DNA code is copied into an RNA molecule Translation The interpretation of the code from mRNA into the language of proteins (amino acids) Transmutation The transformation of a stable nucleus into the nucleus of another element by bombarding the nucleus with protons, neutrons, or other small particles Unsaturated (a) In a molecule—having a double or triple bond, allowing the molecule to pick up atoms in an addition reaction; (b) in a solution—able to contain more solute at a given temperature Urea (ornithine) cycle A series of reactions in the liver that produce urea, the final end-product of amino acid catabolism Valence The "combining capacity" of an atom; the number of single bonds an atom can form Valence shell The outermost energy level of an atom Vapor The gaseous form of a substance that normally exists as a liquid or solid Virus A particle consisting of nucleic acid surrounded by a protein covering Viscosity The resistance of a substance to flow Vitamin A biologically active organic substance needed in trace quantities for normal health and growth Volume A measure of the amount of space occupied by a substance Wax The ester of a fatty acid with a high molecular weight alcohol X ray A form of radiation that is generated when a beam of electrons strikes a metal plate in an evacuated tube

7

carbidedeuteriufilamenthelidehydridehydrogeoxide

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