Chapter 1 & Chapter 2 - Chemistry and Life

3/9/13 Chapter 1 & Chapter 2 - Chemistry and Life

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Chapter 1 & Chapter 2 - Chemistry and Life

Due: 2:00pm on Friday, February 8, 2013

Note: You will receive no credit for late submissions. To learn more, read your instructor's Grading Policy

Chapter 4 Pre-Test Question 1

Part A

Most organic compounds contain carbon and _____.

Hint 1.

Think about the chemical formulas for methane and glucose.

ANSWER:

Correct

In fact, some argue that carbon dioxide should not be considered an organic molecule because it does not contain hydrogen.

Chapter 4 Question 2

Part A

The complexity and variety of organic molecules is due to

ANSWER:

Correct

Carbon Bonding and Functional Groups

Hydrocarbons are molecules consisting of only carbon atoms and hydrogen atoms. Hydrocarbons form the basis of many types of organic molecules.In addition to carbon atoms and hydrogen atoms, many organic molecules also have groups of atoms called functional groups. These functional groupsmay be substituted for one or more of the hydrogen atoms of a hydrocarbon. The functional groups present in an organic molecule determine thechemical behavior of that molecule.

Part A - Carbon bonding

Which molecules show an appropriate number of bonds around each carbon atom?

Biol 1002 - Spring 2013

Chapter 1 & Chapter 2 - Chemistry... Resources

oxygen

nitrogen

phosphate

sulfur

hydrogen

the variety of rare elements in organic molecules.

their tremendously large sizes.

the chemical versatility of carbon atoms.

the fact that they can be synthesized only in living organisms.

their interaction with water.

Signed in as Nora Trejos Help Close



Select the three that apply.

Hint 1. Formation of bonds with carbon

A carbon atom has a total of six electrons. Four of a carbon atom's six electrons are located in the outermost shell (valence shell).

Since the valence shell of a carbon atom can hold a total of eight electrons, a carbon atom would need to gain or lose four electrons tocomplete its valence shell and form an ion. Instead, a carbon atom usually completes its valence shell by sharing its four electrons, formingcovalent bonds with other atoms.

Carbon atoms are tetravalent, meaning they form a total of four covalent bonds. A carbon atom may form different combinations of single,double, or even triple bonds as long as the total number of bonds around a carbon atom is four.

Hint 2. Single, double, and triple bonds

The table below shows how a single covalent bond, a double covalent bond, and a triple covalent bond between two general atoms, A and B,would be represented in a structural formula.

Type of bond Example

single bond

double bond

triple bond

A single bond indicates that two electrons are being shared between two atoms.A double bond indicates that four electrons are being shared between two atoms.A triple bond indicates that six electrons are being shared between two atoms.

Hint 3. Which combinations of single and double bonds are possible around a carbon atom?

Which combinations of single and double covalent bonds result in the appropriate number of bonds around a single carbon atom?

Select the three that apply.

ANSWER:

ANSWER:

3 single bonds

3 single bonds and 1 double bond

2 double bonds

2 single bonds and 1 double bond

4 single bonds



Correct

Since carbon atoms are tetravalent (able to form four bonds), atoms may branch off a carbon atom in as many as four places. The ability of acarbon atom to form four different bonds allows carbon to form many different sizes and types of molecules. Carbon atoms may form chains,rings, or combinations of chains and rings. The tetravalence of carbon makes it particularly well-suited to forming the backbone of a hugediversity of organic molecules.

Part B - Identifying functional groups in a molecule

The molecule shown here contains four functional groups.

Highlight all the atoms of the four functional groups by clicking on them. When you click on each atom, it will change color. Todeselect an atom, click on it again. Do not highlight any bonds.

Hint 1. Definition of functional group

A functional group is a specific configuration of atoms commonly attached to the carbon skeleton of an organic molecule. Functional groupsconfer specific chemical properties to the molecules of which they are a part. Atoms typically found in functional groups include oxygen,nitrogen, sulfur, and phosphorus.

Hint 2. Chemical structures of functional groups

The table below shows the formulas of six biologically important functional groups.

Functional group Formula

hydroxyl

carbonyl

carboxyl

amino

sulfhydryl

phosphate

Hint 3. Can you highlight the functional group of a molecule?

The molecule shown here contains a hydroxyl functional group.

Highlight the atoms of the hydroxyl group ( ) by clicking on them. When you click on each atom, it will change color. To



deselect an atom, click on it again. Do not highlight any bonds.

ANSWER:

ANSWER:

Correct

A functional group is a group of atoms bonded together in a specific way that can replace a hydrogen atom in a hydrocarbon. The moleculeshown here contains four functional groups ( , , , and ) attached to a carbon chain that is six carbon atoms long.

Part C - Classifying molecules by their functional groups

Functional groups confer specific chemical properties to the molecules of which they are a part. In this activity, you will identify which compoundsexhibit certain chemical properties as well as examples of those six different compounds.

Drag one molecule (white label) and one chemical property (blue label) to each bin.

Hint 1. Organic compounds and their functional groups

The table below shows the formulas of six biologically important functional groups and the compounds in which they are found. Inaldehydes, the carbonyl group is at the end of the carbon skeleton, whereas in ketones, it is within the carbon skeleton.

Compound Functional group Formula

alcohol hydroxyl

aldehyde or ketone carbonyl



carboxylic acid carboxyl

amine amino

thiol sulfhydryl

organic phosphate phosphate

ANSWER:

Correct

Some biologically important functional groups include the hydroxyl group, the carbonyl group, the carboxyl group, the amino group, thesulfhydryl group, and the phosphate group. Phosphate groups, for example, are an important part of the structure of ATP (adenosinetriphosphate), an energy storage molecule in cells.

Activity: Making and Breaking Polymers

Click here to complete this activity.

Then answer the questions.

Part A

What name is given to the process seen in this animation?To view the animation, click here. Then click on the image to start the animation.

ANSWER:



Correct

The linking of the monomers involves the removal of water.

Activity: Carbohydrate Structure and Function

Click here to view this animation.


Part A

Which molecule is not a carbohydrate?

Hint 1.

What are some common complex carbohydrates?

ANSWER:

Correct

A lipid is a hydrophobic polymer, not a carbohydrate.

Part B

Which of the following statements about monosaccharide structure is true?

Hint 1.

How do monosaccharides differ from one another?

ANSWER:

hydrolysis

dehydration synthesis

catabolism

monomerization

water formation

Glycogen

Lipid

Cellulose

Starch



Correct

This statement is true.

Part C

True or false? Peptidoglycan is a polysaccharide found only in bacteria.

Hint 1.

Which polysaccharide is found only in bacteria?

ANSWER:

Correct

Part D

Which complex carbohydrate contains only a-1,4-glycosidic linkages?

Hint 1.

This carbohydrate has an unbranched structure.

ANSWER:

Correct

Amylose is formed from a-1,4-glycosidic linkages of glucose.

Part E

Which of the following complex carbohydrates is listed with its correct function?

Hint 1.

Review the functions of the common complex carbohydrates.

ANSWER:

Aldoses and ketoses differ in the position of their hydroxyl groups.

Monosaccharides can be classified according to the spatial arrangement of their atoms.

All monosaccharides contain carbon, hydrogen, oxygen, and nitrogen atoms.

A six-carbon sugar is called a pentose.

True

False

Amylose

Amylopectin

Cellulose

Glycogen



Correct

Cellulose is indeed the main structural component of plant cells walls.

Part F

Which polysaccharide contains a modified monosaccharide?

Hint 1.

This polysaccharide is found mainly in bacterial cell walls.

ANSWER:

Correct

The N-acetylglucosamine and N-acetylmuramic acid units that make up peptidoglycan are composed of modified glucose monomers.

Amino Acid Functional Groups

Amino acids are the building blocks of proteins. There are 20 amino acids that most commonly occur in proteins. Based on the functional group makingup their side chain, or R group, amino acids are classified as acidic, basic, or neutral. The physical and chemical properties of the R group determinethe unique characteristics of each amino acid.

Acidic amino acids have acidic R groups. Their electrically charged R groups make these molecules highly soluble in water.Basic amino acids have basic R groups. Their electrically charged R groups make these molecules highly soluble in water.Neutral (neither acidic nor basic) amino acids can be further classified as nonpolar or polar. The neutral nonpolar amino acids have Rgroups that contain no charged atoms; most of these amino acids are not water soluble. The neutral polar amino acids have R groups thathave a dipole moment. The partial charges in their R groups make these molecules generally water soluble.

It important for you to understand how amino acids are classified, rather than just looking up the answers to this tutorial in your book. The hints providedhere will teach you how to figure out the classifications without looking them up. That way you won't have to memorize them when you are tested onthis material.

Part A - Classifying amino acids I

Classify these amino acids as acidic, basic, neutral polar, or neutral nonpolar.

Drag each item to the appropriate bin.

Hint 1. How to approach the problem

Every amino acid has a carboxylic acid group, an amino group, an -carbon, and an R group. Look at the R group to classify the amino

acid.

Acidic R groups contain a carboxylic acid functional group, -COOH.

Chitin: constituent of bacterial cell walls

Starch: primary energy-storage molecule in animals

Amylose: main component of plant starch

Cellulose: structural component of plant cell walls

Cellulose

Starch

Peptidoglycan

Glycogen



Basic R groups contain an amino (not amide) functional group, -NH2, which attracts a proton to form -NH3.Neutral polar R groups are neither acidic nor basic, but they contain a highly electronegative atom such as oxygen, nitrogen,or sulfur.Neutral nonpolar R groups contain mostly carbon and hydrogen (alkyl groups). They may also contain nitrogen or sulfur, butthe effect of those atoms is diminished due to the size of the alkyl portion.

You should also keep in mind the different behaviors of acids and bases: acids can donate H+ ions; bases can accept H+ ions.

Hint 2. What type of amino acid is alanine?

The R group on alanine is -CH3. Classify alanine based on its R group.

ANSWER:

Hint 3. What type of amino acid is arginine?

The R group on arginine is -(CH2)3NHC(NH2)NH, which becomes

-(CH2)3NHC(NH2)N+H2 at pH=7. Classify arginine based on its R group.

ANSWER:

Hint 4. What type of amino acid is asparagine?

The R group on asparagine is -CH2CONH2 . Classify asparagine based on its R group.

ANSWER:

Hint 5. What type of amino acid is cysteine?

The R group on cysteine is -CH2SH. Classify cysteine based on its R group.

ANSWER:

Hint 6. What type of amino acid is glutamine?

The R group on glutamine is -CH2CH2CONH2. Classify glutamine based on its R group.

ANSWER:

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar



ANSWER:

Correct

The composition of an amino acids R group characterizes whether that amino acid is neutral (polar or nonpolar), acidic, or basic, anddetermines how it interacts in cells. Arginine, with its reactive R group, is often found at the active sites of enzymes, where it participates inchemical reactions.

Part B - Classifying amino acids II





acid.

Acidic R groups contain a carboxylic acid functional group, -COOH.Basic R groups contain an amino functional group (not amide), -NH2 (which attracts a proton to form -NH3).Neutral polar R groups are neither acidic nor basic, but contain a highly electronegative atom such as oxygen, nitrogen, orsulfur.Neutral nonpolar R groups contain mostly carbon and hydrogen (alkyl groups). They may also contain nitrogen or sulfur, buttheir effect is diminished due to the size of the alkyl portion.

Hint 2. What type of amino acid is lysine?

acidic

basic

neutral polar

neutral nonpolar



The R group on lysine is -CH2CH2CH2CH2NH2, which becomes

-CH2CH2CH2CH2N+H3 at pH=7. Classify lysine based on its R group.

ANSWER:

Hint 3. What type of amino acid is methionine?

The R group on methionine is -CH2CH2SCH3. Classify methionine based on its R group.

ANSWER:

Hint 4. What type of amino acid is phenylalanine?

The R group on phenylalanine contains an aromatic ring composed entirely of carbon and hydrogen atoms. Classify phenylalanine based onits R group.

ANSWER:

Hint 5. What type of amino acid is proline?

The R group on proline is composed entirely of hydrogen and carbon atoms. Classify proline based on its R group.

ANSWER:

Hint 6. What type of amino acid is serine?

The R group on serine is -CH2OH. Classify serine based on its R group.

ANSWER:

ANSWER:

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar



Correct

The structure of the amino acid R group determines the identity and character of amino acids. The amino acid phenylalanine is classified as anonpolar amino acid. In addition, it is known as an aromatic amino acid because of the ring structure of its R group.

Part C - Classifying amino acids III





acid.

Acidic R groups contain a carboxylic acid functional group, -COOH.Basic R groups contain an amino functional group (not amide), -NH2 (which attracts a proton to form -NH3).Neutral polar R groups are neither acidic nor basic, but contain a highly electronegative atom such as oxygen, nitrogen, orsulfur.Neutral nonpolar R groups contain mostly carbon and hydrogen (alkyl groups). They may also contain nitrogen or sulfur, butthe effect of these atoms is diminished due to the size of the alkyl portion.

You should also keep in mind the different behaviors of acids and bases: acids can donate H+ ions; bases can accept H+ ions.

Hint 2. What type of amino acid is threonine?

The R group on threonine is -CH(OH)CH3. Classify threonine based on its R group.

ANSWER:

acidic

basic

neutral polar

neutral nonpolar



Hint 3. Classify tyrosine

The R group on tyrosine is composed of an aromatic ring with an -OH group. Classify tyrosine based on its R group.

ANSWER:

Hint 4. What type of amino acid is tryptophan?

The R group on tryptophan is a two-ring system composed almost entirely of hydrogen and carbon atoms. Classify tryptophan based on itsR group.

ANSWER:

Hint 5. What type of amino acid is valine?

The R group on valine is -CH2(CH3)2. Classify valine based on its R group.

ANSWER:

Hint 6. What type of amino acid is glutamic acid?

The R group on glutamic acid is -CH2CH2COOH, which becomes -CH2CH2COO- at pH=7. Classify glutamic acid based on its R group.

ANSWER:

ANSWER:

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar

acidic

basic

neutral polar

neutral nonpolar



Correct

R group composition classifies amino acids and determines their function. For example, the amino acid tryptophan is a nonpolar amino acid. Itis also known as an aromatic amino acid because of the structure of its R group, and it is closely related to the neurotransmitter serotonin,which often occurs in low amounts in individuals suffering from depression.

The Double Helix

DNA, or deoxyribonucleic acid, contains the genetic information that is used by all living things to produce their biomolecules essential for life. DNA is adouble helix, with two strands. The two strands are held together by hydrogen bonds between complementary nitrogenous bases. The two strands arealways complementary, ensuring that the DNA can be replicated accurately. The two complementary DNA strands always run in opposite directions:One runs from 5' to 3', and the other runs from 3' to 5', if you are looking along the strand, as seen in the image.

Part A

Pair up the nucleotide bases with their complementary partners.


Hint 1. The difference between purines and pyrimidines

The complementary partners in a DNA base pair are always made up of one purine and one pyrimidine, never two purines or twopyrimidines. Purines are the nucleotides that have the double-ring structures. Pyrimidines are the nucleotides that have the single-ringstructures. An easy way to think of it is that the longer names (pyrimidines) have the smaller rings, and the shorter name (purines) have thebigger rings.



Hint 2. Distinguish purines from pyrimidines

Distinguish the purines from the pyrimidines.


ANSWER:

ANSWER:

Correct

In a DNA sequence, the purine adenine always pairs with the pyrimidine thymine, and the purine guanine always pairs with the pyrimidinecytosine.

Part B



Write the complementary sequence for the following DNA sequence, in order from 3' to 5':

Use all capital letters to write the DNA sequence.

Hint 1. The definition of a complementary sequence

Each of the four nucleotides found in DNA has one complementary partner. Adenine ( ) always pairs with thymine ( ) and guanine ( )

always pairs with cytosine ( ) on the complementary DNA strand. The two complementary strands always pair up, each strand running in

opposite directions. Below is an example of a DNA sequence and its complement.

Sequence

Complement

Hint 2. Select the complementary sequence

As an example, select the complementary sequence for the following:

ANSWER:

ANSWER:

Correct

Part C

Rank the following base pairs according to their stability.

Rank from most to least stable. To rank items as equivalent, overlap them.

Hint 1. Hydrogen bonds and base-pair stability

In general, the stability of a base pair is determined by the number of hydrogen bonds between the two bases. The more hydrogen bondsbetween the bases, the more stable the base pair is.

Hint 2. Determine the number of hydrogen bonds between bases

Which of the three base pairs has the largest number of hydrogen bonds between the bases?

ANSWER:

GCTATAACTCGATTCGAA



ANSWER:

Correct

The base pair adenine-cytosine occurs very rarely in nature. It only happens during a mutation event. When the DNA is replicated, one of thetwo daughters will contain a guanine-cytosine base pair in the location of the mutation, and the other daughter will contain an adenine-thyminebase pair.

adenine-thymine

adenine-cytosine

guanine-cytosine



Chemistry Review - Reactions & Equilibrium: Chemical Equations

Review the Chemical Equations tutorial.


Part A

Which statement about the following reaction is true? 4 Fe + 3 O2 2 Fe2O3

ANSWER:

Correct

Correct! You identified the reactants as Fe and O and the product as Fe2O3. You also knew that the coefficients in the equation correspond tothe number of atoms or molecules that take part in the reaction.

Part B

Choose the appropriate balanced equation for the following chemical reaction. C6H6 + H2 C6H12

ANSWER:

Correct

Correct! You balanced the equation appropriately by making sure that the same quantity of each element appears on both sides of the arrow.

Part C

Choose the correct balanced equation for the following reaction. C8H18 + O2 CO2 + H2O

ANSWER:

Four atoms of Fe react with 3 molecules of O2 to form 2 molecules of Fe2O3

The reaction is not balanced.

Four grams of Fe reacts with 3 grams of O2 to form 2 grams of Fe2O3.

Fe2O3 is the reactant in this reaction.

None of the above.

C6H6 + 3 H2 C6H12

2 C6H6 + 6 H2 2 C6H12

C6H6 + 6 H2 C6H12

C6H6 + 6 H2 2 C6H12

None of the above.

4 C8H18 + 50 O2 32 CO2 + 36 H2O

2 C8H18 + 25 O2 16 CO2 + 18 H2O

C8H18 + 12.5 O2 8 CO2 + 9 H2O

C8H18 + 17 O2 8 CO2 + 18 H2O

None of the above.



Correct

Correct! This equation has every element balanced and has the smallest possible whole number coefficients.

Chemistry Review - Reactions & Equilibrium: Chemical Reactions

Review the Chemical Reactions tutorial.


Part A

Which of the following is a chemical reaction?

ANSWER:

Correct

Good work! A chemical reaction alters the covalent bonding between atoms, making new kinds of molecules. That doesn't happen in any ofthe events listed here.

Part B

What kind of chemical reaction is shown in this animation below?

ANSWER:

Melting ice.

Dissolving a lump of sugar in a cup of coffee.

Changing a carbon atom to a nitrogen atom by radioactive decay.

Making a hydrogen bond between a water molecule and a sugar molecule.

None of the above.

Addition

Decomposition

Polymerization

Isomerization

None of the above.



Correct

Yes! Two kinds of reactions occur here: hydrolysis (which consumes water) and condensation (which produces water). In both, two reactantmolecules trade parts to make two product molecules. Informally, we call them transfer reactions.

Part C

Potential energy is always ...

ANSWER:

Correct

Right! Potential energy occurs in many forms, but it's always associated with the arrangement of objects in space. Often the objects exertforces on each other.

Part D

Which of the following is true of activation energy?

ANSWER:

Correct

Yes! In a collision, thermal energy is converted to potential energy.

Part E

Which fact is most important in explaining how molecules convert thermal energy to activation energy (EA)?

ANSWER:

Correct

Good work! In a collision, kinetic energy becomes the potential energy of distortion, which can weaken bonds enough to permit a reaction.

Part F

Which statement is true of the transition state?

ANSWER:

associated with position or arrangement.

associated with chemical reactions.

associated with motion.

the energy of chemical bonds.

energy that could exist but is not yet present.

(a) Molecules usually get it from thermal energy.

(b) Molecules usually get it by breaking bonds.

(c) It's the energy difference between reactants and products.

Both (a) and (c).

(a), (b), and (c).

Thermal energy is a form of potential energy.

Potential energy decreases when molecules make bonds.

Distortion increases a molecule's potential energy.

Distortion decreases a molecule's potential energy.

Potential energy increases when molecules make bonds.



Correct

Right! It's an arrangement that quickly breaks apart, emitting either the original molecules or new product molecules.

Chemistry Review - Acids, Bases, & pH: Buffers

Review the Buffers tutorial.


Part A

Which statement is true of pH buffers?

ANSWER:

Correct

Yes! By using weak acids and bases, the buffer can absorb or give off H+, stabilizing the pH.

Part B

A buffer consists of undissociated acid (HA) and the ion made by dissociating the acid (A-). How does this system buffer a solution againstdecreases in pH?

ANSWER:

(a) It can break apart to yield either reactants or products.

(b) It is extremely unstable and lasts only an instant.

(c) It has less potential energy than the reactants but more than the products.

Both (a) and (b).

Both (b) and (c).

(a) They consist of strong acids and strong bases.

(b) They keep the pH of the blood constant.

(c) They consist of weak acids and weak bases.

Both (a) and (b).

Both (b) and (c).

(a) HA dissociates and releases H+ and A- into solution.

(b) A- reacts with H+ to become HA.

(c) As the solution loses H+, HA replaces the lost H+.

Both (a) and (c).

None of the above.



Correct

Yes! A- binds most of the added H+, so not much H+ is left to lower the pH.

Part C

Buffers work best when ...

ANSWER:

Correct

Great choice! That arrangement gives the least change in pH when either acid or base is added.

Part D

How does the way a buffer stabilizes pH during addition of acid differ from the way the same buffer stabilizes pH during addition of base?

ANSWER:

Correct

Good choice! The buffer accepts H+ in one case; it gives off H+ in the other case.

Part E

Which answer helps to explain why all living cells need pH buffers?

ANSWER:

Correct

Correct! When these side chains ionize, they exert forces that affect the protein's folding. Thus, if pH isn't stabilized, the proteins will changetheir folding and may not function properly. To see the role of carboxyl and amino groups, see the lesson on Ionic Forces in Tertiary Structure,in the Proteins section.

Part F

To make a buffer, you need to ...

ANSWER:

the pH is nearly neutral.

5% nearly all of the buffer molecules are dissociated.

the ratio of H+ to OH- is close to 1.0.

about half of the buffer molecules are dissociated.

nearly all of the buffer molecules are undissociated.

In one case it adds H+; in the other case it adds OH-.

The same buffer can't work for both acid and base.

It's the same reaction running backward or forward.

In one case the buffer is strong; in the other case it's weak.

Amino acid side chains have many carboxyl and amino groups.

Hydrogen bonds only form at medium pH values.

ATP will not deliver energy if it is ionized.

Nucleic acids must have positive charges to form double helices.

All of the above.



Correct

Right! When half of the molecules are ionized, there are plenty of molecules that can either absorb H+ or give off H+ when the pH is disturbedfrom outside.

Activity: Heritable Information: DNA

Click here to complete this activity.


Part A

DNA is composed of building blocks called _____.

ANSWER:

Correct

DNA is a composed of nucleotide units.

Part B

In eukaryotic cells DNA has the appearance of a _____.

ANSWER:

Correct

Eukaryotic DNA is organized as a double helix.

(a) combine equal amounts of a strong acid and a strong base in water.

(b) put either a strong acid or a strong base in water.

(c) adjust the pH to 7.0.

(d) have a weak acid or a weak base half ionized in water.

Both (a) and (c).

nucleic acids

Gs

nucleotides

adenines

amino acids

single strand

letter U

double helix

triple helix

circle




Part A

Organisms interact with their environments, exchanging matter and energy. For example, plant chloroplasts convert the energy of sunlight to

ANSWER:

Correct


Part A

To understand the chemical basis of inheritance, we must understand the molecular structure of DNA. This is an example of the application ofwhich concept to the study of biology?

ANSWER:

Correct


Part A

Which taxonomic domain includes multicellular photosynthetic organisms?

Hint 1.

The kingdoms of life are grouped into three higher levels of classification called domains.

ANSWER:

carbon dioxide and water.

oxygen.

kinetic energy.

chemical energy.

the energy of motion.

evolution

feedback regulation

the cell theory

emergent properties

reductionism

Bacteria

Plantae

Fungi

Archaea

Eukarya



Correct

Plants and certain algae are multicellular photosynthetic organisms included in the kingdom Plantae of the domain Eukarya.


Part A

Competition is central to the theory of natural selection. Why does competition occur?

Hint 1.

Think about some of Darwin's fundamental observations.

ANSWER:

Correct

Resource competition is one of the main ingredients for natural selection. Organisms must compete for limited resources, and only the bestadapted will survive and reproduce.


Part A

Which of the following is an example of "unity in diversity"?

Hint 1.

Consider how certain characteristics help to distinguish scientific inquiry from nonscientific ways of describing and explaining nature.

ANSWER:

Correct

These are all examples of unity in diversity.

Score Summary:

Your score on this assignment is 144%.You received 8.74 out of a possible total of 10 points, plus 5.67 points of extra credit.

Males must defend their territories.

Females must choose among possible mates.

Organisms are naturally antagonistic.

Organisms typically produce too many offspring, and resources are limited.

All of the above are correct.

The structure of DNA is the same in all organisms.

All organisms, including prokaryotes and eukaryotes, use essentially the same genetic code.

Cilia and flagella in all eukaryotes have the same basic structure.

The forelimbs of all mammals have the same basic structure, modified for different environments.

All of the above are correct.

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Chapter 1 & Chapter 2 - Chemistry and Life