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Mississippi science Grade 8

Guided Reading and Study Workbook

Prentice Hall Science

explorer

Answer Key

000200010270667947_CH00_FM_pi-iv 3/7/11 11:30 AM Page ii

000200010270667949_CH00_FM_pi-v 2/8/11 3:21 PM Page i

Mississippi scienceGrade 8

Prentice Hall Science

explorer

Taken from:

All-in-One Teaching Resources, Prentice Hall Science Explorer: Human Biology and Health All-in-One Teaching Resources, Prentice Hall Science Explorer: Inside Earth

All-in-One Teaching Resources, Prentice Hall Science Explorer: Weather and ClimateAll-in-One Teaching Resources, Prentice Hall Science Explorer: Environmental Science

All-in-One Teaching Resources, Prentice Hall Science Explorer: Cells and HeredityAll-in-One Teaching Resources, Prentice Hall Science Explorer: From Bacteria to Plants

All-in-One Teaching Resources, Prentice Hall Science Explorer: Chemical Building BlocksAll-in-One Teaching Resources, Prentice Hall Science Explorer: Sound and Light

All-in-One Teaching Resources, Prentice Hall Science Explorer: The Nature of Science and TechnologyAll-in-One Teaching Resources, Prentice Hall Science Explorer: Astronomy

All-in-One Teaching Resources, Prentice Hall Science Explorer: Motion, Forces, and Energy

Guided Reading and Study Workbook

Answer Key

Cover photographs courtesy of iStockPhoto.

Taken from:

All-in-One Teaching Resources, Prentice Hall Science ExplorerCopyright © 2005 by Pearson Education, Inc.Published by Prentice HallBoston, Massachusetts 02116

All rights reserved. No part of this book may be reproduced, in any form or by any means, without permission inwriting from the publisher.

This special edition published in cooperation with Pearson Learning Solutions.

All trademarks, service marks, registered trademarks, and registered service marks are the property of their respectiveowners and are used herein for identification purposes only.

Pearson Learning Solutions, 501 Boylston Street, Suite 900, Boston, MA 02116A Pearson Education Companywww.pearsoned.com

000200010270667949

CP/LP

ISBN 10: 0-558-81651-7ISBN 13: 978-0-558-81651-3

000200010270667949_CH00_FM_pi-iv 3/7/11 11:32 AM Page ii

Contents

Technology and Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 C

Unit 1 Physical ScienceElements and the Periodic Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 CMotion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 CThe Electromagnetic Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 C

Unit 2 Life ScienceViruses and Bacteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 CProtists and Fungi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 CGenetics: The Science of Heredity . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 CChanges Over Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 CBones, Muscles, and Skin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 CFood and Digestion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 CCirculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 CRespiration and Excretion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 CThe Nervous System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 C

Unit 3 Earth ScienceEarthquakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 CVolcanoes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 CThe Atmosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 CWeather Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 CWeather Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 CLand, Water, and Air Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 CEnergy Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 CStars, Galaxies, and the Universe . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 C

© Pearson Education, Inc. All Rights Reserved.

iii

000200010270667949_CH00_FM_pi-v 2/17/11 9:13 AM Page iii

“Technology and Engineering” taken from All-in-One Teaching Resources, Prentice HallScience Explorer: The Nature of Science and Technology

“Elements and the Periodic Table” taken from All-in-One Teaching Resources, PrenticeHall Science Explorer: Chemical Building Blocks

“Motion” taken from All-in-One Teaching Resources, Prentice Hall Science Explorer:Motion, Forces, and Energy

“The Electromagnetic Spectrum” taken from All-in-One Teaching Resources, PrenticeHall Science Explorer: Sound and Light

“Viruses and Bacteria” and “Protists and Fungi” taken from All-in-One TeachingResources, Prentice Hall Science Explorer: From Bacteria to Plants

“Genetics: The Science of Heredity” and “Changes Over Time” taken from All-in-OneTeaching Resources, Prentice Hall Science Explorer: Cells and Heredity

“Bones, Muscles, and Skin,” “Food and Digestion,” “Circulation,” Respiration andExcretion,” and “The Nervous System” taken from All-in-One Teaching Resources,Prentice Hall Science Explorer: Human Biology and Health

“Earthquakes” and “Volcanoes” taken from All-in-One Teaching Resources, PrenticeHall Science Explorer: Inside Earth

“The Atmosphere,” “Weather Factors,” and “Weather Patterns” taken from All-in-OneTeaching Resources, Prentice Hall Science Explorer: Weather and Climate

“Land, Water, and Air Resources” and “Energy Resources” taken from All-in-OneTeaching Resources, Prentice Hall Science Explorer: Environmental Science

“Stars, Galaxies, and the Universe” taken from All-in-One Teaching Resources, PrenticeHall Science Explorer: Astronomy

© Pearson Education, Inc. All Rights Reserved.

iv

000200010270667949_CH00_FM_pi-v 2/23/11 12:33 PM Page iv

ANSWER KEYTechnology and Engineering

Understanding Technology Guided Reading and Study Use Target Reading SkillsSample answers:Q. What does technology have to do with sci-ence?A. Advances in technology contribute to advances in science.Q. How does science affect technology?A. Advances in science contribute to advances in technology.1. Technology is how people change the world around them to meet their needs or to solve practical problems.2. a, b, d3. true4. To improve the way people live5. Communication technology; Telephone6. Manufacturing technology; Oven7. Biological and chemical technology; Detergent8. Energy and power technology; Lamps9. Construction technology; House or apart-ment building10. Transportation technology; Car or bicycle11. Science is the study of the natural world to understand how it functions, while technology modifies the natural world to meet human needs.12. a, d13. false14. a, b15. obsolete16. false17. A technology in use at the present time18. emerging19. A technology that is old but still in use20. b21. a22. d23. c24. d25. They are made of parts that work together.26. goal, inputs, processes, outputs, feedback27. goal28. Something that is put into a system in order to reach a goal29. process30. output31. Information a system uses to monitor the input, process, and output so that the system can adjust itself to meet the goal.32. Inputs include turning on the gas, setting the temperature, and putting in food to cook. Outputs include heat being released and cooked food.

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Technology Design Skills Guided Reading and Study Use Target Reading SkillsIdentify the need.Research the problem.Design a solution.Build a prototype.Troubleshoot and redesign.Communicate the solution.1. a, b, c2. true3. engineer4. They clearly define the problem they are try-ing to solve.5. They gather information that will help them in their tasks.6. a. books, articles b. conferences c. experi-ments d. people7.8. The solution stage involves coming up with ideas, or thinking about different ways to solve a problem. Engineers weigh many possible solutions and choose the best one.9. true10. b11. c12. a13. sketches, models14. true15. The trade-off is strength for appearance.16. A working model used to test a design17. b, c, d18. false19. To address any problems with the design20. troubleshooting21. consumers22. a, c, d.23. A legal document issued by a government that gives the inventor exclusive rights to make, use, or sell the invention for a limited time24. permission25. true

rue

Technology and Society Guided Reading and Study Use Target Reading SkillSample answer:Cause Invention of steam-powered loomsEffects Positive effect: greater productionNegative effect: loss of jobs

1 C

t

ANSWER KEYTechnology and Engineering

© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.

Cause Pesticide applicationEffects Positive effect: protects cropsNegative effect: harmful to plants and animalsCause Invention of tractorsEffects Positive effect: can plow more landNegative effect: loss of farm jobsCause Invention of computers, electronic equip-ment, and powerful machineryEffects Positive effect: workers can do moreNegative effect: quickens pace of life1. Any group of people who live together in an area, large or small, and have certain things in common, such as a form of government2. technology3. Inventions of the Iron Age enabled farmers to grow more food. As food supplies increased, many people moved to towns and cities.4. b, c5. false6. true7. Technological advances have made farm

land using a tractor. Bad impacts include the expense of farm equipment, which some farm-ers cannot afford.

8. a. filling with gases b. saving lives c. causing injuries9. a, c, d10. People must analyze its possible risks and benefits.11. risks; benefits12. The risks include head injury; the benefits include comfortable to wear, good appearance.13. a, b, c14. One value may favor a technology, while another value cautions against it.15. true

Key Terms1. prototype2. feedback3. constraint4. troubleshooting5. input6. process7. obsolete8. goal9. engineer10. systemAnswer: technology


jobs easier. For example farmers can plow more

2 C

UNIT

1

Physical Science

ANSWER KEY

Elements and the Periodic Table


Introduction to Atoms Guided Reading and Study

Use Target Reading Skills

Sample questions and answers:

Q.

What particles are in the center of an atom?

A.

Protons and neutrons.

Q.

What particles move around the outside of the nucleus?

A.

Electrons.

1.

false

2.

a.

nucleus

b.

neutron

c.

proton

d.

electron

3.

The number of protons in an atom equals the number of electrons. The positive charge from the protons balances the negative charge from the electrons, making the atom neutral.

4.

true

5.

protons and neutrons

6.

protons

7.

The atomic number is the number of pro-tons in the nucleus.

8.

Isotopes are atoms with the same number of protons but with different number of neu-trons.

9.

Student diagrams should indicate any two of the following: An isotope of carbon with a mass number of 12 has 6 protons, 6 neutrons, and 6 electrons. An isotope of carbon with a mass number of 13 has 6 protons, 7 neutrons, and 6 electrons. An isotope of carbon with a mass number of 14 has 6 protons, 8 neutrons, and 6 electrons.

10.

a, b, c, d

11.

Sample answer: Scientists use models to describe atoms because they are so small. Mod-els of atoms are also used to explain how matter behaves.


Organizing the Elements Guided Reading and StudyUse Target Reading SkillsSample questions and answers:Q. What pattern of elements did Mendeleev discover?A. Patterns appeared when the elements were arranged in order of increasing atomic mass.

Q. What data about elements is found in the periodic table?A. Atomic number, chemical symbols and names, and average atomic mass.Q. How are elements organized in the periodic table?A. Elements are organized in periods and groups based on their properties.

1. He recognized a set of patterns that applied to all elements.

2. The atomic mass of an element is the aver-age mass of all the isotopes of that element.

3. Patterns appeared when he arranged the elements in order of increasing atomic mass.

4. true5. three6. in a regular, repeated pattern7. periodic table8. atomic number9. Each calcium atom has 20 protons and 20

electrons.

10. chemical symbol11. a. Tin

b. Snc. 118.69d. 50

12. The properties of an element can be predi-cated from its location in the periodic table.13. period14. true15. b, c16. nitrogen17. b

Metals Guided Reading and StudyUse Target Reading SkillsSample answers: What You Know 1. Metals are shiny.2. Metals are magnetic.3. Metals are hard.4. Metals bend.5. Jewelry is made from metal.What you Learned1. Ductile metals can be pulled into a wire.2. Alkali metals react by losing one electron.3. Gold is a transition metal.

5 C

ANSWER KEY

Elements and the Periodic Table


4.

Many lanthanides are used in alloys.

5.

New elements are made in particle accelera-tors.

1.

properties

2.

c

3.

d

4.

c

5.

b

6.

a

7.

magnetic

8.

true

9.

corrosion

10.

The reactivity of metals tends to decrease as you move from left to right across the peri-odic table

11.

a, b

12.

sodium and potassium

13.

a, b, c

14.

magnesium and calcium

15.

a, b, c

16.

true

17.

false

18.

They are placed below the periodic table.

19.

alloys

20.

They are located below the lanthanides

21.

22.

a.

Alkali

b.

Alkaline

c.

Transitiond. Lanthanides

23. They are synthesized when nuclear parti-cles are forced to crash into one another.24. Curium.25. false


uranium

Nonmetals and Metalloids Guided Reading and StudyUse Target Reading SkillsSample answers: What You Know 1. Nonmetals are not shiny.2. Nonmetals are not magnetic.3. Carbon is nonmetal.4. Some nonmetals are gases.5. Nonmetals are on the right side of the peri-odic table. What you Learned1. Nonmetals are dull and brittle.2. Nonmetals react with other elements by gain-ing or sharing electrons.3. Neon is a noble gas.

4. Metalloids have characteristics of metals and nonmetals.5. Metalloids have a varying ability to conduct electricity.

Pe

rio

dic

Ta

ble

1. nonmetals2. They are located to the right of the zigzag

line in the green-tinted boxes.3. true4. a, b5. compounds6. b7. All living things contain compounds that

are made of long chains of carbon atoms.8. d9. nitrogen gas

10. diatomic molecule11. d12. a, c, d13. b14. true15. b, d16. a. Group 14; Carbon

b. Group 15; Nitrogen, phosphorusc. Group 16; Oxygen, sulfur, seleniumd. Group 17; Fluorine, chlorine, bromine,

iodinee. Group 18; Helium, neon, argon, kryp-

ton, xenon, radon17. A hydrogen atom has only one proton and one electron.18. The chemical properties of hydrogen differ very much from those of other elements.19. Metalloids are elements that have some characteristics of both metals and nonmetals. 20. silicon21. Their most useful property is their varying ability to conduct electricity.22. Semiconductors are substances that can conduct electricity under some conditions but not under other conditions.

Elements From Stardust Guided Reading and StudyUse Target Reading SkillsSample answers: a. Fusion continues until the star's core is mostly iron.b. The massive star forms a supernova and fusion creates the heaviest elements.

1. Plasma consists of a gas-like mixture of free electrons and atoms stripped of electrons.

6 C

ANSWER KEYElements and the Periodic Table


2. nuclear fusion3. heavier elements4. Hydrogen5. a6. berrylium7. helium and carbon8. false9. A nebula is a cloudlike region of gases that

form when a star like the sun shrinks and its ele-ments blow away.10. iron11. A supernova is a huge explosion that breaks apart a massive star.12. elements


Key Terms1. supernova2. malleable3. corrosion4. neutron5. period6. metalloid7. ductile8. plasma9. noble gases

10. nucleus11. Answer: periodic table

7 C

ANSWER KEY

Motion


Describing and Measuring Motion Guided Reading and Study


This is one possible way to complete the graphic organizer. Accept all logical answers.

What You Know

A moving object changes position.You can measure how far something moves.Some things move faster than others.

What You Learned

You need to compare motion to a reference point.The meter is the SI unit for distance.Speed can be calculated and graphed.

1.

motion

2.

A reference point is a place or object used for comparison to determine if something is in motion.

3.

reference point

4.

International System of units; Meter; One thousandth

5.

100

6.

1,000

7.

Speed = Distance/Time

8.

Divide the total distance the cyclist trav-eled by the total time.

9.

velocity

10.

The direction in which it is moving.

11.

slope

12.

true

13.

1,400 m

14.

The jogger traveled no distance during these minutes; the jogger stopped.


Slow Motion on Planet EarthGuided Reading and StudyUse Target Reading SkillsSample questions and answers:Why is the motion of plates shown over such large time spans? (Because the plates move very slowly)How has the position of North America changed over time? (North America has moved away from Africa and Europe over time.)

1. false2. plates3. According to this theory, Earth’s plates

move very slowly in various directions.4. Circled: a, b, and d

5. true6. Scientists can estimate how the continents

moved in the past and how they may move in the future.

7. Distance = Speed � Time8. false

�

Acceleration Guided Reading and StudyUse Target Reading SkillsSample answers:

Main Idea: In science acceleration refers to speeding up, slowing down, or changing direc-tion.Detail: A softball accelerates when it is thrown, because it speeds up.Detail: A softball accelerates when it is caught, because it slows down.Detail: A soft ball accelerates when it is hit with a bat, because it changes direction.

1. Acceleration is the rate at which velocity changes.

2. speed, direction3. acceleration4. true5. acceleration6. true7. Circled: a, b, and d8. The moon is accelerating because it is con-

stantly changing direction as it revolves around Earth.

9. (in left column) Speeding up (in right col-umn) Decreasing speed; Changing direction10. The change in velocity during each unit of time.11.velocity) / Time12. false13. Circled: a, b, and d14. The speed increases over time.15. The acceleration is constant.

Acceleration = (Final velocity–Initial

8 C

ANSWER KEY

Motion


�

Key Terms

A B C

=

=

=

=

=

== =

D E F

G H I

6 1 8

7 5 3

2 9 4

15 15 15

15

15

15

15

15


9 C

ANSWER KEYThe Electromagnetic Spectrum


The Nature of Electromagnetic Waves Guided Reading and Study Use Target Reading SkillsNature of Electromagnetic WavesI. What is an electromagnetic wave?

A. Producing electromagnetic wavesB. EnergyC. Speed

II. Models of electromagnetic wavesA. Wave model of lightB. Particle model of light

1. Electromagnetic waves are transverse waves that transfer electrical and magnetic energy.

2.3. Vibrating electric and magnetic fields that

move through space at the speed of light4. Electric field: A region in which charged

particles can be pushed or pulledMagnetic field: A region in which magnetic

forces are present5. electromagnetic radiation6. a, c, d7.8. particles9. Only some waves can pass through.

10. polarized light11. It has the properties of a wave.12.13. photoelectric effect14. energy15. Photons

Pearson Education, Inc. All Rights Reserved.

true

false

false

©

Waves of the Electromagnetic Spectrum Guided Reading and Study Use Target Reading Skill This is one possible way to complete the graphic organizer. Accept all logical answers.

The Electromagnetic SpectrumQ. Which electromagnetic waves have the shortest wavelength?A. Gamma rays have the shortest wavelength.Q. Which electromagnetic waves have the low-est frequency?A. Radio waves have the lowest frequency.

1. a, c, d2. a, b, c3. The electromagnetic spectrum4. a. Radio waves b. Infrared rays c. Ultravio-

let rays d. X-rays e. Gamma rays5. Radio waves6. Sound7.8.9. radar

10. Infrared rays11. a, b, c12. thermogram13. visible light14. a. Red b. Orange c. Yellow d. Green e. Blue f. Violet15.16. ultraviolet rays17. a, c, d18. X-rays19. a20. Gamma rays21. They have the greatest amount of energy.22. a, b, c23. Gamma rays from objects in space are blocked by Earth's atmosphere.

10 C

truetrue

true

ANSWER KEYThe Electromagnetic Spectrum


Producing Visible Light Guided Reading and Study Use Target Reading Skill This is one possible way to complete the graphic organizer. Accept all logical answers.

Light bulbs

Feature Ordinary Light Bulb

Tungsten-Halogen

Fluorescent Light

Vapor Light Neon Light

Bulb material Glass Quartz Glass Glass Glass

Hot/cool Hot Hot Cool Hot Hot

Color of light White White White Yellow or bluish white

Red

Efficiency (low, medium, high)

Low Medium High High —

1. a. Illuminated b. Luminous2. spectroscope3. incandescent light4. An incandescent light bulb that has a tung-

sten filament and contains a halogen gas such as iodine or bromine

5. a, b, d6.7. b, c, d8. fluorescent9. When an electric current passes through

the bulb, it causes the gas inside to give off ultra-violet rays. When the ultraviolet rays hit the powder in the tube, the powder gives off visible light.10. a, b11. a, b, d12. neon light13. a, b, d


true

©

Wireless Communications Guided Reading and Study Use Target Reading Skill This is one possible way to complete the graphic organizer. Accept all logical answers.

What You Know1. Cellular phones don’t use wires.2. Radio and television signals travel through

air.

What You Learned1. The signals for radio and television pro-

grams are carried by radio waves.2. The signals can be transmitted by changing

either the amplitude or the frequency of the radio waves.

3. Cellular phones transmit and receive sig-nals using microwaves.

1.2. Amplitude modulation3. a. electronic signals b. amplitude c. elec-

tronic signals (or sounds)4. Frequency modulation5. They travel as modulations, or changes, in

the frequency of the wave.6.7. FM waves have more energy than AM

waves. As a result, FM waves pass through the atmosphere, instead of being reflected back as AM waves are.

8. Television broadcasts carry picture signals as well as sound signals. To do this, television signals use both frequency and amplitude mod-ulation, rather than one or the other as in radio signals.

9. a. Very High Frequency (VHF) b. Ultra High Frequency (UHF)10. d

11 C

true

false


ANSWER KEYThe Electromagnetic SpectrumS

pe

ctru

m

11. Each cell has one or more towers.12. You can also use cellular phones to page someone, to send short text messages and video as a digital camera, or to get information from the Internet.13.14. a, c, d


true

©

15. To make sure that only people who pay for the programs and have a decoding box can use the signal16. A system of navigation, using a network of satellites that broadcast radio signals to Earth17. You could determine your exact position on Earth's surface or in the air.

Key Terms1. radiation2. photon3. radio waves4. microwaves5. polarized6. thermogram7. visible light8. X-rays9. illuminated

10. luminous11. incandescent lights12. fluorescent lights

12 C

UNIT

2 Life Science


ANSWER KEY

Viruses and Bacteria

V

Viruses Guided Reading and Study


One way students might organize the informa-tion is: How Active Viruses Multiply —

1.

Virus attaches to surface of living cell

2.

Virus injects genetic material into cell

3.

Cell produces viral proteins and genetic material

4.

Viruses assem-ble.

5.

Cell bursts, releasing viruses. How Hidden Viruses Multiply —

1.

Virus attaches to cell

2.

Virus injects its genetic mate-rial

3.

Virus’s genetic material becomes part of cell’s genetic material

4.

Later, virus’s genetic material becomes active

5.

Cell produces viral proteins and genetic material; viruses are assembled

6.

Cell bursts, releasing viruses

1.

Viruses are not cells. They do not use energy to grow or to respond to their surroundings. They cannot make or take in food or produce wastes.

2.

false

3.

b.

host

4.

parasites

5.

Viruses can infect all organisms.

6.

true

7.

false

8.

bacteriophage

9.

true

10.

nanometers

11.

A virus can be named after the disease it causes, the location where it was first found, or after people who first identified the virus.

12.

b.

They need to be inside a living cell in order to reproduce.

c.

They can be named after people.

13.

a.

Protein coat,

b.

Genetic material

14.

a.

It protects the virus.

b.

It allows the virus to attach to certain cells in the host.

15.

true

16.

b

17.

a

18.

b

19.

true

20.

cold, flu, AIDS

21.

false

22.

Viruses are used as a “messenger service” to deliver genetic materials to cells that need it.


Bacteria Guided Reading and StudyUse Target Reading Skills.

One way students might organize the informa-tion is: Students may write one or two descrip-tive phrases to help them remember the key term. Call on students to share their definitions.

1. prokaryotes2. true3. a. spherical, b. rodlike, c. spiral4. c. ribosomes5. a. Flagellum, b. Genetic material,

6. false7. a. Capture and use the sun’s energy, b. Use the energy from chemical substances in their environment8. Heterotrophic bacteria eat other organisms or the food that other organisms make.9. false10.

11. Bacteria form endospores when conditions in the environment become unfavorable for growth.12. b. As autotrophic bacteria use the sun’s energy to produce food, they release oxygen into the air. c. Bacteria help produce foods such as cheese, apple cider, and olives.13. decomposers14. true

Reproduction in Bacteria

Asexual Reproduction

Sexual Reproduction

Name of Process

Binary fission Conjugation

Number of Parents

One Two

What Occurs in Process

The cell duplicates its genetic material. Then the cell divides into two separate cells.

One bacterium transfers some of its genetic material into another though a thin, threadlike bridge that joins the cells.

Result of Process

New cells identical to parents

Bacteria that are genetically different from parents

c. Ribosome , d. Cell membrane, e. Cell wall,

15. a. Digest food, b. Make vitamins, c. Prevent harmful bacteria from attaching to the intestines16. People with some types of diabetes cannot make their own insulin. Bacteria can be engi-neered to produce human insulin. Insulin-making bacteria are grown in vats. The insulin they produce is then purified and made into medicine.

15 C

s


ANSWER KEY

Viruses and Bacteria

Vir

use

s a

nd

Ba

cte

ria

�

Viruses, Bacteria, and Your Health Guided Reading and Study


Possible answers include:

What You Know

1.

You can catch a cold from somebody who has one.

2.

Some diseases can be treated with medicines.


What You Learned1. You can catch diseases through contact with an infected person, a contaminated object, an infected animal, or an environmental source.2. Antibiotic resistance results when some bacteria are able to survive in the presence of an antibiotic.1. An illness that can pass from one organism to another is an infectious disease.2. a. Infected person, b. Contaminated object, c. Infected animal, d. Environmental source3. They can enter through breaks in the skin, moist linings in the eyes, ears, nose, mouth, or other body openings. They can also be inhaled or swallowed.4. false5. Examples include drinking from a cup used by an infected person, touching an object that an infected person sneezed or coughed on, or eat-ing food contaminated by an infected person.6. b7. a

8. c9. true10. c. Clostridium tetani11. It is a chemical that can kill bacteria without harming a person’s cells.12. Many bacteria have become resistant to antibiotics. They can survive and reproduce in the presence of antibiotics.13. false14. true15. Diseases include tetanus, measles, polio, and chickenpox.16. a, b, d17. Answers include get plenty of rest, follow the doctor’s recommendations, and try not to infect others.

Key Terms1. bacteriophage2. virus3. conjugation4. parasite5. respiration6. cytoplasm7. flagellum8. antibiotic9. endospore10. host11. toxin12. ribosome13. vaccine

Answer: binary fission

16 C


ANSWER KEY

Protists and Fungi

Pro

tis

ts a

nd

Fu

ng

i

Protists Guided Reading and Study


ProtistsI. What Is a Protist?II. Animal-Like Protists

A. Protozoans With PseudopodsB. Protozoans With CiliaC. Protozoans With FlagellaD. Protozoans That Are Parasites

III. Plantlike ProtistsA. DiatomsB. DinoflagellatesC. EuglenoidsD. Red AlgaeE. Green AlgaeF. Brown Algae

IV. Funguslike ProtistsA. Slime Molds

B. Water MoldsC. Downy Mildews

1.

a, d

2.

a.

animal-like protists,

b.

plantlike protists,

c.

funguslike protists

3.

b, c

4.

protozoan

5.

The amoeba extends a pseudopod on each side of the food particle. The two pseudopods join together, trapping the particle inside.

6.

c

7.

true

8.

c

9.

a

10.

b

11.

false

12.

parasites

13.

false

14.

algae

15.

autotrophs

16.

Diatoms—Unicellular; Glasslike cell walls; move by gliding in slime oozed from slits in their cell wallsDinoflagellates—Unicellular; Surrounded by stiff plates, variety of colors, two flagellaEuglenoids—Unicellular; Green; can be het-erotrophs; have flagellaRed Algae—Multicellular; Red pigment; found at deep ocean depthsGreen Algae—Both; colonies; Green; live in fresh or salt water or moist areas on landBrown Algae—Multicellular; Green, yellow, orange, and brown pigments; plantlike struc-tures; live in cool, rocky water

17.

a, c

18.

a.

slime molds,

b.

downy mildews,

c.

water molds

19.

Most live in water or moist places.

20.

b, c


Algal Blooms Guided Reading and StudyUse Target Reading SkillsSaltwater blooms—Effects: toxins concentrated in fish and shellfish that eat algae can cause ill-ness to people and other large organisms when they consume the fish or shellfish. Freshwater blooms—Causes: Nutrients build up, causing a rapid increase in algae growth; Effect: Fish and other organisms in the water die.1. a, d2. a. An increase of nutrients in the water; b. An increase in ocean temperature3. The algae produces toxins that become concen-trated in the fish and shellfish that eat the algae. When people or other organisms eat the fish and shellfish, they can become seriously ill or even die.4. eutrophication5. sunlight, die, Bacteria, oxygen, die, oxygen

Fungi Guided Reading and StudyUse Target Reading SkillsPossible questions and answers are:What are fungi? (Fungi are eukaryotes that have cell walls, are heterotrophs that feed by absorb-ing their food, and use spores to reproduce.)How do fungi reproduce? (Fungi usually repro-duce by making spores.)What is the role of fungi in nature? (Fungi are important decomposers and recyclers.)1. b, c2. Examples include cricket-killing fungus, bread mold, mushrooms, yeast, and bracket fungi.3. hyphae

4. false5.

Cap

Hyphae

Underground hyphae

Stalk

Gills

17 C


ANSWER KEY

Protists and Fungi

Pro

tis

ts a

nd

Fu

ng

i

6.

Hyphae from the fungus grow into a food source. Digestive chemicals ooze from the hyphae into the food. The digestive chemicals break down the food so the hyphae can absorb it.

7.

true

8.

spores

9.

budding

10.

true

11.

a. sac fungi, b. club fungi, c. zygote fungi

12.

decomposers

13.

true

14.

antibiotics

15.

The fungi’s hyphae grow among the plant’s roots and absorb water and nutrients from the soil for the plant.

16.

lichen; water and minerals; food

� � �

Key Terms

A.

6

B.

1

C.

8

D.

7

E.

5

F.

3

G.

2

H.

9I. 4All column, row, and diagonal sums = 15


18 C


ANSWER KEYGenetics: The Science of HeredityG

enetics:

of H

eredity

Mendel’s Work Guided Reading and StudyUse Target Reading Skills Mendel’s WorkCheck students’ outlines to make sure they include significant details. The beginning of the outlines should resemble the following:I. Mendel’s experiments

A. Crossing pea plants1. crossed plants with contrasting traits2. used only purebred plants

1. heredity2. c3. a4. b5. pistil; stamens6. offspring of many generations that have the same trait7. short; tall; tall; short8. d9. round; wrinkled10. b, c11. true12. c13. a14. b15. capital16. lowercase17. Tt18. false

Probability and Heredity Guided Reading and StudyUse Target Reading SkillsCall on volunteers to read their definitions aloud. Make sure that students have explained the definitions in their own words.1. probability2. a, b, c3. false4. No, the results of the first five tosses do not affect the results of the sixth toss.5. He always found that about three fourths of the plants had tall stems and one fourth of the plants had short stems.6. predict7. Punnett square


8. b9. c10. a11. d12. hybrid13. true14. heterozygous

The Cell and Inheritance Guided Reading and StudyUse Target Reading SkillsOne possible way to complete the graphic organizer:Detail: Grasshoppers: 24 chromosomes in body cells, 12 in sex cellsDetail: Fertilized egg has 24 chromosomes.Detail: Alleles exist in pairs in organisms.1. a, d2. Genes are carried from parents to their off-spring on chromosomes.3. Meiosis is the process by which the number of chromosomes is reduced by half to form sex cells—sperm and eggs.4. two; separate, two; four5. meiosis6. false7. Half the sperm cells will have the T allele and the other half will have the t allele.8. 239. Genes are lined up in the same order on both chromosomes.

TT

T

t

tT

Tt

Tt tt

Tt

Tt

19 C


ANSWER KEYGenetics: The Science of HeredityG

enetics:

of H

eredity

The DNA Connection Guided Reading and StudyUse Target Reading SkillsPossible ways to complete the graphic organizer:DNA provides code to form messenger RNA.�

Messenger RNA attaches to ribosome.�

Transfer RNA “reads” the messenger RNA.�

Amino acids are added to the growing protein.1. a, b2. a. adenine (A); b. thymine (T); c. guanine (G); d. cytosine (C)3. The genetic code is the order of nitrogen bases along a gene that specifies what type of protein will be produced.4. amino acid5. gene, protein6. ribosomes7. DNA: Thymine; Both: Cytosine; RNA: Goes out into the cytoplasm, Uracil8. a. Messenger RNA copies the coded message from the DNA in the nucleus and carries the message to the ribosome in the cytoplasm. b. Transfer RNA carries amino acids to the ribo-some and adds them to the growing protein.

9. d10. b11. A mutation is any change in a gene or chromosome.12. Mutations can cause a cell to produce an incorrect protein during protein synthesis.13. b, c14. variety15. false16. helpful17. environment


Key Terms1. meiosis2. Punnett square3. phenotype4. messenger RNA5. heterozygous6. probability7. dominant allele8. trait9. gene10. genetics11. purebredWhat Mendel studied: inheritence

20 C

ANSWER KEYChanges Over Time


Darwin’s Theory Guided Reading and StudyUse Target Reading Skills1. Possible answers:CausesOverproduction: More offspring are produced than can survive.Variations: Members of the same speciesdiffer.Competition: Offspring compete for survival.Selection: Some variations make individuals better fit for survival.Environmental Change: Changes can affect an individual’s survival.Genes: Genes that determine survival are passed from parent to offspring.1. false2. species3. fossil4. true5. a, c6. organisms7. b8. a9. adaptation10. b, c, d11. c12. natural selction13. false14. b15. c16. a17. true18. false

Evidence of Evolution Guided Reading and StudyUse Target Reading SkillsPossible answers: Theory—Evolution; Evi-dence—Fossils show that organisms that lived in the past were very different from organisms alive today; Patterns of early development show that some different organisms look similar dur-ing their early stages; Similar body structures in different species show that the organisms shared a common ancestor.


homologous structuresAll have a tail and tiny slits in their throats

during early development.These animal groups all have a similar body

structure—an internal skeleton with a back-bone.

1.2.

3.

true

shrew is more closely related to elephants than to rodents because the elephant shrew’s DNA is more similar to that of elephants.

b, c

-

The Fossil Record Guided Reading and StudyUse Target Reading SkillsHave students write what they know about each key term before reading the definitions in the section. Explain that connecting what they already know about key terms helps them to remember the terms. As they read each passage that contains key terms, remind them to write the definitions in their own words.1. a, b2. true3. sediments4. petrified5. a, c, d6. false7. true8. relative dating, radioactive dating9. oldest, younger10. true11. radioactive12. The half-life is the time it takes for half of the atoms in a sample to decay.13. argon–4014. Scientists compare the amount of a radioac-tive element in a sample to the amount of the element into which it breaks down. This infor-mation is used to calculate the age of the fossil.15. fossil record16. false17. Scientists use the fossil record.18. a19. The three eras are the Paleozoic, the Meso-zoic, and the Cenozoic.20. the extinction of many types of organisms at the same time21. Evolution occurs slowly but steadily.YesEvolution occurs during short periods of rapid changes separated by long periods of little or no changes.No

6.

5.4.

7. true8.

Scientists have learned that the elephant

Members of a species may be separated bya river, a volcano, or a mountain range.

21 C

ANSWER KEYChanges Over Time


Key TermsDown1. evolution4. adaptation6. selection8. mold

Across2. variation3. gradualism5. homologous7. equilibria9. fossil10. species11. extinct


22 C


ANSWER KEYBones, Muscles, and Skin

an

d S

kin

Body Organization and Homeostasis Guided Reading and StudyUse Target Reading SkillsBody Organization and HomeostasisI. Cells

A. Structures of cellsB. Functions of cells

II. TissuesIII. Organs and organ systemsIV. Homeostasis

A. Homeostasis in actionB. Maintaining homeostasisC. Stress and homeostasis

1. a. cellsb. tissuesc. organsd. organ systems

2. cell3. d4. nucleus5. The cytoplasm is the area between the cell membrane and the nucleus. It contains a clear, jellylike substance in which other cell structures are found.6. true7. A tissue is a group of similar cells that per-form the same function.8. Muscle: Makes parts of the body move by contracting, or shortening; musclesNervous: Carries messages back and forth between the brain and other parts of the body;brain, spinal cord, or nervesConnective: Supports the body and connects all its parts; blood, fat, cartilage, bones, or tendonsEpithelial: Covers the surfaces of the body, inside and out; skin, lining of digestive system9. organ10. c11. true12. An organ system is a group of organs work-ing together to perform a major function.13. d14. f15. c16. a17. e18. b19. homeostasis20. When a person perspires, the liquid evapo-rates and the skin cools down. The removal of heat helps the body maintain a constant body temperature.


The Skeletal System Guided Reading and StudyUse Target Reading SkillsSample answers:What does the skeleton do? (The skeleton pro-vides shape and support, helps you to move, protects organs, produces blood cells, and stores minerals and other materials.)How do joints allow movement? (Joints allow bones to move forward or backward, in a circle, in a rotating motion, and in a gliding motion.) How strong are bones? (Bones can absorb more force without breaking than can granite or concrete.)What can I do to care for my bones? (Eat a well-balanced diet and get plenty of exercise.)1. a. Provides shape and support

b. Enables the body to movec. Protects the internal organsd. Produces blood cellse. Stores certain materials until the body

needs them2. c3. vertebrae4. Muscles pull on the bones to make the body move.5. d6. blood cells7. A joint is a place in the body where two bones come together.8. immovable joints, movable joints9. c10. Allows forward or backward motion; knees and elbowsAllows the bone to swing in a circle; shoulder blades and hipsAllows one bone to rotate around another; neckAllows one bone to slide over another; wrists and ankles11. ligaments12. a, d13. Bone cells form new tissue during growth, in response to the force of the body’s weight, and to heal broken bones.14. a. compact bone

b. bone marrowc. spongy boned. outer membrane

15. d16. a17. b18. c

23 C



21. A combination of a balanced diet and regu-lar exercise will keep the bones healthy.22. osteoporosis


19.20. b, d

true

Diagnosing Bone and Joint Injuries Guided Reading and StudyUse Target Reading SkillsSample answers:Effect on body cells:X-rays—Can cause damageMRI—Causes no damageTypes of injuries identified:X-rays—Bone (fracture and dislocation)MRI—Bone and soft tissueHow they work:X-rays—pass through soft tissue and are absorbed by bone; bone shows on filmMRI—Magnetic energy causes atoms to vibrate, which forms a pattern that can be converted into an imageCost:X-rays—low costMRI—high cost1. c2. a3. b4. false5. X-rays are a form of energy that travels in waves.6. true7. a. X-rays cannot be used to view injuries to soft tissues.b. The energy in X-rays can damage body cells.8. magnetic resonance imaging9. A person is exposed to short bursts of mag-netic energy inside the MRI scanner. The mag-netic energy causes the body’s atoms to vibrate. A computer analyzes the vibration patterns and produces an image of the area.10. a, b11. arthroscope12. false

The Muscular System Guided Reading and StudyUse Target Reading SkillsSample answers:How does skeletal muscle help my body move? (Skeletal muscles are attached to the ends of bones and provide the force to move them.)

Where is smooth muscle found? (On the inside of many internal organs)What are the characteristics of cardiac muscle? (It is found only in the heart; it is like smooth muscle because it is involuntary and like skeletal muscle because it is striated.)

1. a. Involuntary muscles are not under con-scious control.b. Voluntary muscles are under conscious control.2. b3. Attached to bones of skeleton, voluntary, striatedSmooth, involuntary, notOnly in heart, involuntary, striated4. tendon5. true6. heartbeats7. Muscles contract when they receive mes-sages from the nervous system.8. false9. Because muscle cells can only contract, not extend, skeletal muscles must work in pairs. While one muscle contracts, the other muscle returns to its original length.10. contracts, original length

The Skin Guided Reading and StudyUse Target Reading SkillsMain Idea:The skin has several important funcions.Sample details:The skin forms a barrier against disease-causing microorganisms and harmful substances, and prevents the loss of important fluids; the skin helps the body maintain a steady temperature; the skin helps to eliminate wastes through per-spiration; the skin contains nerves that gather information about the environment; skin cells produce vitamin D that helps your body absorb calcium.1. b, d2. true3. They warn you that something in the sur-roundings may have injured you.4. vitamin D5. epidermis6. false7. two weeks8. true9. true10. dermis

24 C



11. a, c, d12. pores13. Follicles are structures in which strands of hair grow within the dermis.14. a healthful diet, limiting sun exposure, keeping skin clean


Key Terms1. skeletal2. pore3. joint4. tendon5. fracture6. marrow7. imaging8. cartilage9. sprainDiagonal word is epidermis.

25 C


ANSWER KEY

Food and Digestion

Food and Energy Guided Reading and StudyUse Target Reading SkillsI. Why You Need Food

A. NutrientsB. EnergyC. Nutritionists’ Recommendations

II. CarbohydratesA. Simple CarbohydratesB. Complex CarbohydratesC. Nutritionists’ Recommendations

III. FatsA. Kinds of FatsB. CholesterolC. Nutritionists’ Recommendations

IV. ProteinsA. Amino AcidsB. Complete and Incomplete Proteins

V. Vitamins and MineralsA. Fat-Soluble and Water-Soluble VitaminsB. Importance of VitaminsC. Importance of Minerals

VI. Water

1. a. The materials for growing and for repair-ing tissues; b. The energy for everything you do

2. true

3. nutrients

4. a. carbohydrates b. fats c. proteins d. vitamins e. minerals f. water

5. calories

6. true

7. energy

8. false

9. b

10. a

11. b

12. a

13. Fats are high-energy nutrients that are made up of carbon, oxygen, and hydrogen.

14. b

15. a. Form part of the structure of cells b. Protect and support internal organs c. Insulate the body to keep in heat

16. Unsaturated Fats: Liquid; Most oils, such as olive and canola oilsSaturated Fats: Solid; Meat and dairy products

17. proteins

18. a. Needed for tissue growth and repair b. Play a part in chemical reactions in cells c. Can serve as a source of energy

19. d

20. false

21. b

22. a

23. a

24. b

25. Vitamins are helper molecules in a variety of chemical reactions within the body.

26. b, c, d

27. minerals

28. Your body gets minerals by eating plant foods or animals that have eaten plants.

29. c

30. d

31. a

32. b

33. water

34. The body’s vital processes—including chemical reactions such as the breakdown of nutrients—take place in water.


Healthy Eating Guided Reading and StudyUse Target Reading SkillsSample questions and answers:Q: What is the Food Guide Pyramid?A: The Food Guide Pyramid classifies food into groups to help people plan a healthy diet.Q: What kind of information can I find on a food label?A: serving size, Calories, Percent Daily Value, and ingredients

1. The Food Guide Pyramid classifies foods into six groups. It also tells how many foods to eat from each group every day.

2. The foods in the bottom level of the pyra-mid—foods from grains, such as bread, cereals, rice, and pasta—should make up the largest part of the diet.

3.4. true5. serving size6. A single serving of this food supplies the

body with 110 Calories of energy.

26 C

true

ANSWER KEY

Food and Digestion


7. The Percent Daily Value shows how the nutritional content of one serving fits into the diet of a person who needs 2,000 Calories each day.

8. false

9. weight

10. It can alert you to substances that have been added to the food that could make you sick.


The Digestive Process Begins Guided Reading and StudyUse Target Reading SkillsSample Answer:What You Know

1. Food is digested in the stomach. 2. The digestive system breaks down food.3. Teeth break foods into small pieces.

What You Learned1. Teeth carry out mechanical digestion. 2. An enzyme in saliva breaks down starches

into sugars.3. Muscle contractions called peristalsis push

food toward the stomach.1. food; blood; wastes2. Digestion is the process by which the body

breaks down food into small nutrient mole-cules.

3. false4. absorption5. These materials are removed from the body

as wastes.6. saliva7. b8. An enzyme in saliva breaks down starch

into sugar molecules.9. b

10. c11. a12. d13. a, c, d14. a. Mucus coats and protects the stomach lining. b. Cells in the stomach lining are quickly replaced.

Final Digestion and Absorption Guided Reading and StudyUse Target Reading SkillsMain Idea: Chemical digestion takes place in the small intestine.Details: Food mixes with enzymes and secre-tions; starches, proteins, and fats are digested chemically. Enzymes and secretions are pro-duced by the small intestine, liver, and pancreas.

1. Almost all chemical digestion and absorp-tion of nutrients takes place in the small intestine.

2. a. small intestine; b. liver; c. pancreas3. liver4. bile5. The gallbladder stores the bile produced

by the liver and delivers it to the small intestine.6. starches, proteins, fats7. villi8. true9. true

10. Absorb water into the bloodstream; Pre-pare undigested food for elimination11. rectum12. b

Key Terms1. pancreas2. mucus3. vitamin4. absorption5.6. gallbladder7. enzyme8. saturated fat9. Key Term: nutrient

Definition: A nutrient is a substance in food that provides the raw materials and energy the body needs to carry out all its essential processes.

MyPyramid Plan

27 C

ANSWER KEYCirculation


The Body’s Transport System Guided Reading and StudyUse Target Reading SkillsBottom oval: Left side of heart; Left oval: Body1. circulatory2. blood vessels; blood3. Needed substances, waste products, disease fighting cells4. Each time the heart beats, it pushes blood through the blood vessels of the cardiovascular system.5. Upper: atria; two; to receive blood that comes into the heart. Lower: ventricles; two, to pump blood out of the heart6. valve7. pacemaker; oxygen8. It makes the heart contract at a normal rate.9. arteries, capillaries, veins10. Blood is pumped from the right atrium to the right ventricle and then to the lungs. In the lungs, blood picks up oxygen and releases car-bon dioxide. Blood then flows to the left atrium.11.

12. aorta

Arteryto body

Leftatrium

Rightatrium

Vein frombody

Artery tolungs

Rightventricle Left

ventricle

Blood vesselsin body

Blood vesselsin lungs

Vein fromlungs


A Closer Look at Blood Vessels Guided Reading and StudyUse Target Reading SkillsSample answers:Artery: Carries blood away from heart; Thick walls consisting of three cell layers with thick muscle in the middle layer

Capillary: Exchange of materials between the blood and body cells; Thin walls consisting of one cell layerVein: Carries blood back to the heart; Thick walls consisting of three cell layers with thin muscle in the middle layer1. heart2. false3. b, c4. true5. In the capillaries, materials are exchanged between the blood and the body’s cells.6. diffusion7. Veins carry blood back to the heart.8. a. Contraction of nearby skeletal muscles; b. Valves that prevent blood from flowing back-ward; c. Breathing movements that squeeze veins in the chest9. Blood pressure is the pressure that blood exerts against the walls of blood vessels.10. c

Blood and Lymph Guided Reading and StudyUse Target Reading SkillsSample details: Plasma is the liquid part of blood; red blood cells take up oxygen and deliver it to cells in the body; white blood cells fight disease; platelets help form blood clots.1. plasma2. White blood cells; Platelets3. water4. a. nutrients; b. chemical messengers; c. wastes5. Red blood cells pick up oxygen in the lungs and carry it to cells in the body.6. Hemoglobin is an iron-containing protein that binds chemically to oxygen molecules. It is found in red blood cells.7. They fight disease.8. a. There are fewer of them. b. They are big-ger. c. They have nuclei. d. Most live for months or even years. 9. true10. Fibrin weaves a net of tiny fibers across a cut, which traps blood cells and platelets that form a clot.11. A blood transfusion is the transfer of blood from one person to another.

28 C


ANSWER KEYCirculationC

ircu

latio

n


12. Type A blood has clumping proteins that act against the marker molecules on type B blood cells.13. The Rh factor is a marker on red blood cells that determines whether a person’s blood type is Rh positive or Rh negative.14. b15. d16. a17. c18. The lymphatic system is a network of veinlike vessels that returns fluid to the bloodstream.19. lymph20. Lymph nodes filter the lymph, trapping bacteria and other microorganisms that cause disease.

Cardiovascular Health Guided Reading and StudyUse Target Reading SkillsPossible questions and answers include:Q. What are some cardiovascular diseases?A. atherosclerosis, hypertensiongQ. How can a person keep healthy?A. Exercise regularly, eat a healthy diet, and avoid smoking1. Atherosclerosis is a condition in which an artery wall thickens as a result of the buildup of fatty materials.2. Cholesterol is a waxy, fatlike substance that can restrict the flow of blood in arteriew.3. blood; oxygen; heart attack4. Hypertension is a disorder in which a person’s blood pressure is consistently higher than normal.

5. Hypertension makes the heart work harder and also may damage the walls of the blood vessels.6. Treatment includes regular exercise, careful food choices, limited sodium intake, and medi-cation.7. a. saturated fat; b. trans fats; c. cholesterol8. false9. Exercise strengthens heart muscles. High-fat foods can lead to atherosclerosis; weight gain can strain the cardiovascular system. Smoking increases the risk of heart attack.

Key TermsDown: 1. capillaries, 2. plasma, 3. coronary,8. veinAcross: 4. pacemaker, 5. pulse, 6. atrium, 7. valve, 9. lymph

5p u l

l

a

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4p

a

1c

s

a c e m a

l

2p

a

m

s

k e r

o

3c

6a

r

y

t r i

m9

l p h

u m

n

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e

l7

v8

v

e

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n

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e

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e

29 C


ANSWER KEYRespiration and ExcretionE

xc

retio

n

-

The Respiratory System Guided Reading and StudyUse Target Reading SkillsPossible answers:Path of AirAir enters the noseTo the pharynxTo the tracheaTo the bronchiTo the lungs1. a, d2. a. Move oxygen from the outside environ-ment into the body; b. Remove carbon dioxide and water from the body3. Oxygen4. Respiration is the process in which oxygen and glucose undergo a series of chemical reac-tions inside cells to release energy.5. a. energy; b. carbon dioxide; c. water6. false7. a, c, d8. true9. nostrils; pharynx; trachea; bronchi10. A sneeze shoots particles and bacteria out of the nose and into the air.11. throat12. b13. d14. a15. c16. b, c17. cartilage18. false19. choke20. c21. true22. The blood picks up oxygen from the air inside the alveoli.23. Oxygen passes through the walls of the alveoli and through the capillary walls into the blood. Carbon dioxide and water pass from the blood into the alveoli.24. The alveoli provide a large surface area in a relatively small space.25. false26. The diaphragm is a large, dome-shaped mus-cle that plays an important role in breathing.27. larger; decreases; inhale; smaller; lungs28. larynx29. Vocal cords are folds of connective tissue stretching across the opening of the larynx that produce the voice.

30. Muscles make the vocal cords contract. Air from the lungs rushes through the opening between them. The movement of the vocal cords makes the air vibrate to create a sound.


Smoking and Your Health Guided Reading and StudyUse Target Reading SkillsPossible effects: Damage to protective cilia and risk of cancer due to tar; increase in blood pres-sure and addiction due to nicotine; risk over time of chronic bronchitis, emphysema, lung cancer, and atherosclerosis.1. Tar: Dark, sticky substance that forms when tobacco burns; Clumps cilia together so they can’t keep harmful materials out of the lungsCarbon monoxide: Colorless, odorless gas pro-duced when things are burned; Binds to hemoglo-bin in red blood cells in place of oxygenNicotine: Speeds up the nervous system and heart2. b, c3. a. chronic bronchitis; b. emphysema; c. lung cancer; d. atherosclerosis4. false5. emphysema6. Emphysema is caused when chemicals in tobacco smoke damage lung tissue and breath-ing passages.7. true8. Chemicals from tobacco smoke enter the blood and are absorbed by blood vessels. The chemicals irritate the blood vessels, which causes a buildup of the fatty material that causes atherosclerosis.9. true10. In passive smoking, people involuntarily inhale the smoke from other people’s cigarettes, cigars, or pipes.

The Excretory System Guided Reading and StudyUse Target Reading SkillsPossible student questions and answers are these:Where are nephrons located? (In the kidneys) What three main materials are filtered out of the blood? (Urea, water, glucose) What happens to these filtered materials? (Most of the water and glucose are reabsorbed. Most of the urea remains as urine.)

30 C


ANSWER KEYRespiration and ExcretionE

xc

retio

n

1. The excretory system collects wastes pro-duced by cells and removes the wastes from the body.2. excretion3. urea and excess water4. c5. a6. b7. blood; ureters; urinary bladder; urethra8. Nephrons are tiny structures that remove wastes from blood and produce urine.9. a. Wastes and needed materials are removed from the blood. b. Much of the needed material is returned to the blood and wastes are elimi-nated from the body.10. false11. glucose and water; urea and other wastes

12. Analyzing the contents of urine can detect some medical problems, such as diabetes or kid-ney malfunction.13. water14. false15. a. lungs b. skin; c. liver16. The liver breaks down proteins into urea, and converts part of hemoglobin molecules into substances such as bile.

Key Termsurea, alveoli, bronchitis, nephron, diaphragm, urethra, larynx, tar, cilia, nicotine, kidneyAnswer: respiration


31 C

ANSWER KEY

The Nervous System


How the Nervous System Works Guided Reading and Study


Sample questions and answers:

What is a sensory neuron?

(A neuron that picks up stimuli from the internal or external environment and converts each stimulus into a nerve impulse)

What does an inter-neuron do?

( It carries nerve impulses from one neu-ron to another.)

1.

a.

Receives information;

b.

Responds to information;

c.

Maintains homeostasis

2.

false

3.

a.

the environment;

b.

inside the body

4.

b

5.

false

6.

The nervous system directs the body to respond appropriately to the information it receives.

7.

c

8.

b

9.

d

10.

a

11.

true

12.

nerve

13.

a.

sensory neurons;

b.

interneurons;

c.

brain;

d.

motor neurons

14.

synapse

15.

The axon tips release chemicals that enable the impulse to cross the gap at the synapse.


Divisions of the Nervous System Guided Reading and StudyUse Target Reading Skills Accept all logical definitions for Key Terms.1. true2. brain3. spinal cord4. true5. a. The skull; b. Layers of connective tissue; c. Fluid between layers of connective tissue6. b7. c8. a9. b10. a11. false12. right13. brain; peripheral nervous system14. a. Vertebral column b. Layers of connective tissue c. A watery fluid

15. It consists of a network of nerves that branch out from the central nervous system and connect it to the rest of the body.

16. controls voluntary actions; controls invol-untary actions17. A reflex is an automatic response that occurs very rapidly and without conscious control.18. a, b19. concussion20. Wear a helmet during some activities to help protect your head.21. All the nerve axons in that region are dam-aged, so impulses cannot pass through them, caus-ing loss of movement in some part of the body.

The Senses Guided Reading and StudyUse Target Reading SkillsThe SensesI. Vision

A. How light enters your eyeB. How light is focusedC. How you see an imageD. Correcting nearsightednessE. Correcting farsightedness

II. Hearing and balanceA. How sound is producedB. The outer earC. The middle earD. The inner earE. The inner ear and balance

III. Smell and tasteIV. Touch1. nerve impulses2. b3. e4. d5. c6. a7. false8. a. The image is turned right-side up. b. The images from each eye are combined to form a single image.9.Vision Problems

Questions Nearsightedness Farsightedness

What is wrong?

Cannot see objects that are far away.

Nearby objects look blurry.

What causes it?

The eyeball is too long.

The eyeball is too short.

How is it corrected?

Wear eyeglasses with a concave lens.

Wear eyeglasses with a convex lens.

32 C

ANSWER KEY

The Nervous System


10.

sound

11.

Sounds are made by a material that is vibrating, or moving back and forth.

12.

false

13.

funnel

14.

d

15.

The cochlea is a snail-shaped tube that is lined with receptors that respond to sound.

16.

semicircular canals

17.

true

18.

false

19.

skin

20.

Pain alerts the body to possible danger.


Alcohol and Other Drugs Guided Reading and StudyUse Target Reading SkillsPossible effects: Slowing of central nervous system; sleepiness; slow reaction time1. drug2. drug abuse3. b, d4. tolerance5. c6. true7. Drug users may pay a fine or go to jail. Drug abusers have a hard time doing well in school or keeping a job.8. true9. c

10. e11. a12. d13. b14. b15. true16. digestive17. true18. The abuse of alcohol can cause the destruc-tion of cells in the brain and liver, and it can also lead to addiction and emotional dependence.

19. alcoholism20. true

Key Terms

withdrawalbrain stemdendriteretinairisdepressant

responsecerebrumpupildrugaxonsynapse

Hidden Question: What is a neuron? Answer: A neuron is a nerve cell.

33 C

' Pearson Education, Inc. All Rights Reserved.

UNIT

3 Earth Science

ANSWER KEYEarthquakes


Forces in Earth’s Crust Guided Reading and Study

Use Target Reading Skills Check student defi-nitions for accuracy. 1. b2. volume3a. tension b. compression c. shearing4a. Compression b. Shearing c. Stretches rock d. Squeezes rock e. Rock becomes thinner in the middle f. Rock breaks and slips apart or changes

6. b7. c8. a9. 10. a, d11. a, d12a. Tension b. Compression c. Strike-slip d. Normal e. Horizontal f. Vertical g. Normal and reverse; both have vertical movement. Vertical movement can push up rock. 13. b14. c15. a16. a17. c18. b19. a20. a, b, c21. A large area of flat land elevated high above sea level

Ea

rthq

ua

ke

s


false

©

its shape g. Compression and shearing can both

5. Faultcause rock to break.

Earthquakes and Seismic Waves Guided Reading and Study

Use Target Reading Skills. This is one possible way to complete the graphic organizer. Accept all logical answers. a. P waves compress and expand the ground. b. S waves vibrate from side to side as well as up and down. c. Surface waves produce severe ground movements. 1. focus.2. epicenter.3. vibrations that travel through Earth carrying the energy released during an earthquake.

4. true5. a, b, c6A. P waves B. S waves.7. false8. c9. b10. a11. seismograph.12a. Mercalli scale b. Richter scale c. moment magnitude scale.

14. false15a. a particular seismograph’s location b. the distance from that seismograph to the epicenter

13. b

Monitoring Earthquakes Guided Reading and Study

Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers. a. Drum rotates. b. Pen traces a record of the vibrations.1. The P waves arrive first, followed by S waves, then surface waves. 2a. tiltmeter b. creep meter c. laser-ranging device d. GPS satellite.3. c4. b5. d6. a7a. GPS satellite b. tiltmeter8. laser-ranging device9. GPS satellite10. The waves’ speed and direction change slightly. 11. Geologists use the data to map the fault’s length and depth. They can learn the location of hidden faults12. friction13. false

Earthquake Safety Guided Reading and Study Use Target Reading Skills. This is one possible way to complete the graphic organizer. Accept all logical answers.

37 C

ANSWER KEYEarthquakes


Ea

rthq

ua

ke

s


Earthquake Safety 1. where faults are active and where past earth-quakes have occurred2. d3. The shaking can trigger landslides or ava-lanches. It also can damage or destroy buildings and bridges, topple utility poles, and fracture gas and water mains. It can tear buildings apart.4. the types of rock and soil5. false6. liquefaction; moisture (or water)7. aftershock8. tsunamis9. falling objects and flying glass10. false11. false12. Fasten it to wall studs. 13. Remove heavy items from the walls above beds. Position beds away from windows. 14. Reinforce or strengthen the walls. Plywood panels can strengthen the walls. Metal connec-tors can strengthen the house’s frame. 15. The home should be anchored to solid rock below the soil. 16. It rests on shock-absorbing rubber pads or springs. 17. Earthquakes can cause gas pipes and water mains to break.

Question Answer

Where is the quake risk the highest?

Earthquake risk is the highest along faults and where past earthquakes have occurred.

How do earthquakes cause damage?

Earthquake damage occurs as a result of shak-ing, liquefaction, after-shocks, and tsunamis.

How can you stay safe during an earthquake?

The best way to stay safe during an earthquake is to drop, cover, and hold.

What makes buildingssafer from earthquakes?

New buildings can be made safer from earth-quakes by being built stronger and with greater flexibility. Older buildings can be modified to with-stand stronger quakes.

Key Terms 1. earthquake2. syncline3. compression4. plateau5. stress6. aftershock7. tsunami8. shearing9. anticline10. liquefaction11. footwall12. seismograph

s t i o n s c o d d l n p m

f a e a r t h q u a k e v l

w a f t e r s h o c k n d i

y t o n e e q u r c a f t q

d u p c o s h e a r i n g u

s w n o f s a z s e p t w e

e g o m i p h o r v a d t f

i n m p f g t p u l a c m a

s o d r s y n c l i n e p c

m w c e o m u a q a v b c t

o v e s j m w u c k t i b i

g l n s o t h u m b b e y o

r a t i o k v o o x l e a n

a w o o p l y i m s s a h u

p u f n t t s u n a m i s s

h a l e t a n t i c l i n e

38 C


ANSWER KEYEarthquakesE

arth

qu

ak

es

Connecting Concepts Develop a concept map that uses the key con-cepts and key terms from this chapter. Keep in mind the main idea of this chapter: Forces inside Earth cause rocks to move and to release energy

as seismic waves during an earthquake. The concept map shown is one way to organize how the information in this chapter is related. You may use an extra sheet of paper.

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ault

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g

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aves

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aves

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calli

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39 C

ANSWER KEYVolcanoes


Volcanoes and Plate Tectonics Guided Reading and Study

Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.

Volcanoes and Plate Tectonics

1. a weak spot in the crust where molten mate-rial, or magma, comes to the surface2. magma. 3. lava. 4. a major volcanic belt formed by the many vol-canoes that rim the Pacific Ocean5. along diverging plate boundaries such as mid-ocean ridges and along converging plate boundaries where subduction takes place6. Along the rift valley, lava pours out of cracks in the ocean floor, gradually building new mountains. 7. true8. true9. When the older, denser plate sinks beneath a deep-ocean trench into the mantle, some of the rock above the subducting plate melts and forms magma. Because the magma is less dense than the surrounding rock, it rises toward the surface. Eventually, the magma breaks through the ocean floor, creating volcanoes. Volcanoes can also form where oceanic crust is subducted beneath continental crust.10. island arc. 11. Any three: Japan, New Zealand, Indonesia, the Philippines, the Aleutians, the Caribbean islands12. b13. an area where material from within the man-tle rises and the melts, forming magma14. They formed over millions of years as the Pacific plate drifted over a hot spot. 15. false

Question Answer

Where are volcanoes found?

Volcanoes form along the boundaries of Earth’s plates.

What is a hot spot?

An area where material from deep within the mantle rises and then melts, forming magma

Vo

lca

no

es


Properties of Magma Guided Reading and Study

Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers. Details: Magma is made of elements and compounds, among them silica. Viscosity is a property of magma. Viscosity depends on silica content and temperature. 1. element. 2. true3. b, c 4. slower; lower5. a, d 6. temperature and silica content. 7. b, d 8. rhyolite. 9. basalt. 10. It decreases. 11. pahoehoe. 12. aa. 13a. low b. lower c. higher d. lower e. Possible answer: The lower the temperature and the higher the silica content of magma is, the higher the viscosity of the magma. The higher the tem-perature and the lower the silica content of magma is, the lower the viscosity of the magma.

Volcanic Eruptions Guided Reading and Study

Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.

What You Know

1. Lava flows out of a volcano.

2. Eruptions are not all the same.

3. Some volcanoes are dormant.

What You Learned

1. Magma rises toward Earth’s surface through a pipe

that leads to a vent.

2. Differences in gas and silica content cause some

eruptions to be explosive and others to be quiet.

3. Dormant volcanoes can become active at any time.

40 C

ANSWER KEYVolcanoes


1. true2. true3. a, b 4a. pipe b. crater c. vent d. magma chamber. 5. the area covered by lava as it pours out of a vent6. at the top of the volcano around the central vent7. false

9. a 10. The force of the expanding gases pushes magma from the magma chamber through the pipe until it flows or explodes out of the vent. 11. the magma’s silica content and viscosity12. false13. c 14. a 15. b 16. an explosive eruption that hurls out a mix-ture of hot gases, ash, cinders, and bombs17. false18. Volcanic ash can bury entire towns. If it becomes wet, the heavy ask can cause roofs to collapse. If a jet plane sucks ash into its engine, the engine may stall. Eruptions can cause land-slides and avalanches of mud, melted, snow, and rock. 19. true20. false21a. extinct b. active c. dormant d. extinct, dor-mant, active22. false23. The time between volcanic eruptions may span hundreds to many thousands of years. 24. a, d

V


8a. vent b. side vent c. pipe d. magma

Volcanic Landforms Guided Reading and Study


Volcanic Landforms I. Landforms From Lava and Ash

A. Shield VolcanoesB. Cinder Cone VolcanoesC. Composite VolcanoesD. Lava PlateausE. CalderasF. Soils From Lava and Ash

II. Landforms From MagmaA. Volcanic NecksB. Dikes and SillsC. BatholithsD. Dome Mountains

III. Geothermal ActivityA. Hot SpringsB. GeysersC. Geothermal Energy

1a. shield volcanoes b. cinder cone volcanoes c. composite volcanoes d. lava plateaus. 2. a, b. 3. false4. Mount Fuji in Japan and Mount St. Helens in Washington State5. true6. e. 7. c. 8. b. 9. a. 10. d. 11. potassium, phosphorus12a. volcanic necks b. dikes c. sills d. batholiths e. dome mountains13. Left circle: forms across rock layers; Middle area: forms from magma; Right circle: forms between rock layers14. batholith. 15. the Sierra Nevada mountains in California

17. true18. hot springs. 19. geyser. 20. Steam from underground is piped into tur-bines. Inside a turbine, the steam spins a wheel. The moving wheel in the turbine turns a gener-ator that changes the energy of motion into elec-trical energy.

16. false

Use Key Terms 1. magma. 2. crater. 3. silica. 4. pahoehoe. 5. aa. 6. geyser. 7. volcano. 8. lava. 9. active. 10. caldera. 11. extinct. 12. batholith. 13. dike. 14. sill.

Mars has volcanoes.

41 C

Hidden message:


ANSWER KEYVolcanoesV

Connecting Concepts Forces inside Earth cause magma to heat, move, and push through the crust to erupt as volca-noes that pose hazards and form land features.

This concept map is only one way to represent the main ideas and relationships in this chapter. Accept other logical answers from students.

are

crea

ted

fro

m

Vo

lcan

oes

form

at

mag

ma

mag

ma

colle

cts

in

con

tain

s

is p

lace

wh

ere

wh

ere

mag

ma

reac

hes

su

rfac

e as

isch

arac

teri

zed

by

lead

s to

pip

e

can

har

den

to

fo

rmle

ads

to

exp

losi

ve

silic

a

is s

ite

of

volc

anic

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on

s

volc

anic

nec

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clas

sifi

ed a

s

resu

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s in

resu

lts

inis

low

inis

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h in

det

erm

ined

by

stay

s b

enea

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ical

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igh

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ical

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agm

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lava

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com

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volc

ano


42 C

ANSWER KEYThe Atmosphere

© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.Pearson Education, Inc. All Rights Reserved.©

The Air Around You Guided Reading and StudyUse Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.

1. weather2. Earth’s atmosphere is the envelope of gases that surrounds the planet.3. a. Nitrogen b. Oxygen c. Almost four d. 99%4. b, c, d5. b, d6. a, b7.8. Air contains tiny solid and liquid particles of dust, smoke, salt, and other chemicals.9. water vapor

10.11. Water vapor forms clouds when it con-

denses out of the air to form tiny droplets of water or crystals of ice. The droplets or crys-tals fall as rain or snow if they become heavy enough.

12. The atmosphere contains oxygen and other gases living things need to live. The atmosphere also keeps most of Earth’s surface warm enough for water to exist as a liquid, which living things need, and it protects living things from danger-ous radiation and being hit by objects from outer space.

Air PressureGuided Reading and Study Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.a. Has density. Density is the amount of mass of a substance in a given volume. b. Has pres-sure. Pressure is the force pushing on an area or surface.

What You Know

1. The atmosphere contains oxygen.2. Animals breathe oxygen.

What You Learned

1. The atmosphere contains mostly nitrogen.2. Ozone is a form of oxygen.

1. The weight of the atmosphere itself is con-stantly pressing on your body.

2. a, b, c3. a. increases b. decreases c. increases

d. increases e. Possible answer: If volume stays the same, density increases as mass increases and decreases when mass decreases. If mass stays the same, density increases when volume decreases and decreases when volume increases.

4. barometer5. A mercury barometer contains liquid mer-

cury that is forced up a column when air pres-sure increases. An aneroid barometer has no liquid. The thin walls of its airtight metal cham-ber bulge air when air pressure increases.

6. Students’ lines may be anywhere below the level of the mercury shown in the figure.

7. inches of mercury; millibars8. There are about 1,016 millibars.9. altitude

10.11.12. Air pressure is greater at sea level because sea-level air has the weight of the whole atmo-sphere pressing down on it.13.14. At high elevations, the air is less dense and less oxygen is taken in with each breath. Moun-tain climbers would quickly get out of breath at high altitudes if oxygen tanks were not available.15. d

Layers of the Atmosphere Guided Reading and StudyUse Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.Possible questions and answers include the fol-lowing: Where is the ozone layer? (In the upper stratosphere) Is the thermosphere cold? (No; it is very hot, up to 1,800oC.)

1. temperature2. a, c, d3.4.5. The depth varies from more than 16 kilome-ters above the equator to less than 9 kilometers above the North and South Poles.6.7. It extends to about 50 kilometers above Earth’s surface.8. a, c

43 C

true

true

true

false

false

false

false

false


ANSWER KEYThe AtmosphereT

he

Atm

osp

he

re

10. b, c11. a, b, c12. Energy from the sun strikes the thermo-sphere first, and nitrogen and oxygen molecules in the air convert the energy into heat.13. The thermosphere does not contain enough air molecules to collide with and warm an ordi-nary thermometer very much.14. a. The ionosphere begins 80 kilometers above the surface. b. The exosphere begins about 400 kilometers above the surface.15. auroras


9.face.

It begins 50 kilometers above Earth’s sur-

Air Quality Guided Reading and StudyUse Target Reading SkillsAir Quality

I. Sources of PollutionA. Natural SourcesB. Human Activities

II. Smog and Acid RainA. London-Type SmogB. Photochemical SmogC. Acid Rain

III. Improving Air Quality

1. pollutants2. Air pollution can cause dizziness and head-aches; eye, nose and throat irritation; allergies; coughing; lung disease; and chest pains.3. a, b, c4. Natural sources include molds, plant pollen, forest fires, soil erosion, dust storms, and erupt-ing volcanoes.5. photochemical smog6. a, c, d7. Ozone can irritate the eyes, throat, and lungs. It can also harm plants and other living things and damage certain materials.

8.9. a. sulfur oxide b. water c. acid rain d. Burn-ing high-sulfur coal causes sulfur oxide. e. It is a result of sulfur oxide combining with water. It is a cause of acid rain. f. Trees and other living things are harmed by acid rain.10.11. acid rain12. It may make tree needles turn brown or fall off.13. It can make water so acidic that plants,

vive in it.14.15.

amphibians, fish, and insects can no longer sur-

Use Key TermsA. 2B. 9C. 4D. 7E. 5F. 3G. 6H. 1I. 8

The sums vertically, horizontally, and diagonally add to 15.

44 C

true

true

false

false


ANSWER KEYWeather FactorsW

ea

the

r Fa

cto

rs

Energy in Earth’s Atmosphere Guided Reading and StudyUse Target Reading Skills. This is one possible way to complete the graphic organizer. Accept all logical answers.a. Some of the sun’s energy is reflected back into space or absorbed by gases and particles in the air. b. The remaining energy is absorbed or reflected by the surface. c. Much of the absorbed energy is radiated back into the atmosphere as infrared radiation.1.2. electromagnetic waves3.4. radiation5. a6. c7. b8. The different colors are the result of

different wavelengths.9.

10. a, b, c11. b, d12. It can pass through the atmosphere to the surface.13. Water vapor, carbon dioxide, clouds, dust, and other gases absorb energy from the sun in the atmosphere.14. Clouds, dust particles, and gases reflect energy from the sun.15. scattering16. c, d17. heat18.19. Water vapor, carbon dioxide, methane, and other gases in the air absorb most of the energy that is radiated from Earth’s surface.20. greenhouse effect21.

Heat Transfer Guided Reading and StudyUse Target Reading and SkillsHeat TransferI. Thermal Energy and Temperature

A. Measuring TemperatureB. Temperature Scales

II. How Heat Is TransferredA. RadiationB. ConductionC. ConvectionD. Heating the Troposhpere


true

true

false

false

false

©

1.2. thermal energy3. temperature4.5. thermometer6. When the temperature increases, the liquid

in the bulb expands and rises in the column. When the temperature decreases, the liquid contracts and moves down the column.7. a. 0° b. 100° c. 32° d. 212° e. It is hotter on a

Celsius scale. On a Celsius scale, 50° is midway between 0° and 100° . On a Fahrenheit scale, 50° is much closer to 32° than to 212°8. heat9.

10. conduction11. a, b12. convection13. c14. b15. a16. a. Convection b. Radiation c. Radiation d. Conduction17. convection18. convection currents

Winds Guided Reading and StudyUse Target Reading and Skills Accept all logical answers. Possible answers for Effects:a. Cold, more dense air sinks.b. Dense, cold air has a higher pressure than less dense, warm air. Wind blows from areas of higher pressure to areas of low pressure.1. wind2.3. b4. a5.6. wind-chill factor7. The wind makes you feel colder because it

removes body heat.8. local winds9. Local winds are caused by unequal heating

of Earth’s surface within a small area.10. a11. a. Sea breeze b. Land breeze12. global winds13. a, b, d14. right15. doldrums; horse latitudes

o o o oo

oo o

o

45 C

true

true

true

true

false

ANSWER KEY

Weather Factors


16. a. From the northeast in the Northern Hemisphere and southeast in the Southern Hemisphere b. From the southwest in the Northern Hemisphere and from the northwest in the Southern Hemisphere c. Away from the poles d. Trade winds

17. b, d


Water in the Atmosphere Guided Reading and StudyUse Target Reading and Skills This is one pos-sible way to complete the graphic organizer. Accept all logical answers. How does the water cycle work? (Water evaporates from the surface, condenses to form clouds, and falls to Earth as rain or snow.) What is relative humidity? (The per-centage of water vapor in the air compared to the maximum amount air can hold at that temperature) How do clouds form? (Water vapor in the air con-denses to form liquid water or crystals.) Can you tell about weather conditions by looking at clouds? (Yes; each type of cloud is associated with a different type of weather.)

1. evaporation2. The water cycle is the movement of water

between the atmosphere and Earth’s surface.3. humidity4. It is the percentage of water vapor that is

actually in the air compared to the amount of water vapor the air can hold at a particular temperature.5. a, c6. psychrometer7. d8.9. d

10. c11. b12. a13. b, c, d14. a15. d16. b17. c18. b, d

Precipitation Guided Reading and StudyUse Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.

What You Know1. Precipitation can be rain or snow.2. Precipitation comes from clouds.3. Snowflakes come in many different shapes.

What You Learned

1. Sleet, freezing rain, and hail are forms of precipitation.2. Droplets or ice crystals in clouds must grow heavy enough to fall through the air before precipitation occurs.3. Hail forms inside cumulonimbus clouds.

1. Precipitation is any form of water that falls from clouds and reaches Earth’s surface.2.3. a. Drops of water at least 0.5 mm in diameter

b. Ice particles smaller than 5 mm in diameter c. Ice pellets larger than 5 mm in diameter d. They are similar in that they are all composed

ent sizes; rain is water in liquid form, but sleet and hail are in solid form as ice. e. Rain, sleet, hail f. Hail would cause the most damage.4.5. Mist and drizzle are made up of smaller

drops of water than is rain.6. Freezing rain freezes and builds up as ice

on tree branches, which can then break onto power lines, causing power failures.7. d8. c9. b

10. a11. Large hailstones can cause tremendous damage to crops, buildings, and vehicles.12. droughts13. a, c, d14. rain gauge15.

Key TermsClues down1. heat2. scattering4. convection7. stratus

Clues across3. sea5. temperature6. droughts8. anemometer9. humidity

10. cirrus

of water. They are different in that they are differ-

46 C

true

false

false

false

ANSWER KEYWeather Patterns


Air Masses and FrontsGuided Reading and StudyUse Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.a. Clouds, possibly storms with heavy precipita-tion. b. A warm air mass overtakes a cold air mass. c. Clouds, in light precipitation d. A warm air mass is caught between two cold air masses. e. Clouds, precipitation f. Cold and warm air masses meet, but neither can move the other. g. Clouds, precipitation.1. An air mass is a huge body of air that has

at any given height. 2. temperature; humidity3.4. a. Maritime tropical b. Maritime polar

c. Continental tropical d. Continental polar e. They are alike in that they are both humid. They are different in that the tropical air mass is warm and the polar air mass is cool. f. They aralike in that they are both dry. They are different in that the tropical air mass is warm and the polar air mass is cool.5. west; east 6. As the jet streams blow from west to east,

air masses are carried along their track.7. a. Cold front b. Warm front8. c9. a

10. d11. b12. a, b, c13. cyclone 14.15. Storms and precipitation are associated with cyclones.16.17. Dry, clear weather is generally associated with anticyclones.

StormsGuided Reading and StudyUse Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.a. As air rises, more warm, moist air is drawn into the system, and the hurricane gains energy. b. As winds spiral inward, bands of high winds and heavy rains form.

1. A storm is a violent disturbance in the atmosphere.2. d


e

true

true

false

©

3. lightning 4. b, c 5. flash flood 6. a, b, c 7. A tornado is a rapidly whirling, funnel-

shaped cloud that reaches down from a storm cloud to touch Earth’s surface.8.9. b, c

10.11. The safest place to be is in the basement of a well-built building.12. a, d13. eye 14.15. storm surge 16.17. Snow falls during a storm when the whole

18. b, d 19. You should try to find shelter from the wind, cover exposed parts of your body, and stay dry. If you are in a car, the driver should keep the engine running only if the exhaust pipe is clear of snow.

a. cold b. cools c. Heavy rain

similar temperature, humidity, and air pressure

Predicting the Weather Guided Reading and StudyUse Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.A. A cold front Q. What do the stick symbols indicate? A. Amount of cloud cover, atmo-spheric pressure, wind direction and speed, and temperature Q. What are the slender, curvy lines? A. Isobars, which join places with the same air pressure Q. What does the symbol to the east of Florida mean? A. A hurricane1. meteorologists 2. a, c, d 3. The areas are gathering weather data and

using computers to make forecasts.4. alse

oatmosphere is colder than 0° C.

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true

true

false

f


ANSWER KEYWeather PatternsW

ea

the

r Pa

ttern

s

5. a. Either weather stations or satellitesb. Either weather stations or satellitesc. computer d. meteorologists e. weather fore-cast f. The result of the calculations would change to reflect the revised weather data. g. The forecast prepared by meteorologists would change to reflect the revised calculations pro-duced by the computer.


6. a, b, d 7. b, d 8. The symbols indicate amount of cloud

cover, atmospheric pressure, wind direction, wind speed, and temperature for individual weather stations. Weather maps also show the location of air masses and fronts.9.

1028 millibars, and the wind is from the south-east at 21–25 miles per hour.10. b11. a

12. The symbols show fronts, areas of high and low pressure, types of precipitation, and tem-perature range. 13. rue

Key Terms1. storm2. polar3. maritime4. isobars5. occluded6. tropical7. lightning8. isotherms9. tornado

10. hurricane11. meteorologist

Hidden message: Storms are dangerous.

oThe temperature is 55° F, the air pressure is

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t

ANSWER KEY

Land, Water, and Air Resources


Conserving Land and Soil Guided Reading and Study


Possible answers

include the following:

Detail:

Agriculture—new farmland is created by clearing forests, draining wetlands, and irri-gating deserts.

Detail:

Mining

—

strip mines expose the soil, which can then be blown or washed away more easily.

Detail:

Development—as populations grow, people build more houses and paved roads.

1.

Agriculture; Mining; Development

2.

The rest is too dry, wet, salty, or mountainous.

3.

a.

clearing forests,

b.

draining wetlands,

c.

irrigating deserts

4.

development

5.

a, c

6.

mining

7.

Strip Mining; Underground Mining

8.

false

9.

a, b, c, d

10.

a, b, c, d

11.

b

12.

c

13.

a

14.

bedrock

15.

false

16.

Freezing and thawing break apart the bed-rock. Both plant roots wedged between rocks and chemicals released by lichens break the rock into smaller pieces. Animals such as earth-worms and moles help grind the rock into even smaller particles.

17.

a.

erosion,

b.

nutrient depletion,

c.

desertification

18.

erosion

19.

terracing

20.

nutrient depletion

21.

c

22.

a

23.

b

24.

Desertification is the advance of desertlike conditions into areas that previously were fertile.

25.

true

26.

Crops fail; Soil blows away

27.

land reclamation

28.

true

29.

false

30.

The mining cuts are smoothed out, then the subsoil and topsoil that had been removed before mining are replaced. Finally, grass and trees are planted.


Waste Disposal and Recycling Guided Reading and StudyUse Target Reading Skills Possible questions

and answers include the following:Q. What is the problem with waste disposal?A. Each disposal method has advantages and

disadvantages.

Q. What is recycling?A. Reclaiming raw materials and reusing them

to create new products

Q. How can people help control the solid waste problem?

A. Reduce, reuse, and recycle

Q. Why are some wastes hazardous?A. Some are explosive, flammable, corrosive, or

radioactive.

1. Municipal solid waste is the waste produced in homes, businesses, schools, and other places in a community.2. Other sources include construction debris and certain agricultural and industrial wastes.3. a. burning, b. burying, c. recycling4. a, b5. landfill6. leachate7. Unlike an open dump, a sanitary landfill is constructed to safely hold solid wastes.8. Landfills; Incinerators9. Recycling is the process of reclaiming raw materials and reusing them.10. true11. biodegradable12. a. metal, b. plastic, c. glass, d. paper13. Objects include metal desks, scissors, staples, paper clips, soda cans, house siding, and window screens.14. Products include fiber filling for sleeping bags, fleece jackets, carpeting, park benches, shower stalls, floor tiles, trash cans, and dock pilings.15. false16. Each time paper is recycled, the new paper is rougher, weaker, and darker.

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ANSWER KEY

Land, Water, and Air Resources

ate

r,

an

d A

ir R

eso

urc

es

17.

a, c

18.

Reduce; Reuse; Recycle

19.

composting

20.

Compost can be used as a natural fertilizer for plants.

21.

true

22.

c

23.

a

24.

d

25.

b

26.

true

27.

false

28.

true

29.

a.

burial in landfills,

b.

incineration,

c.

breakdown by living organisms,

d.

storage in deep rock layers

30.

false

31.

They are stored in vaults dug hundreds of meters underground or in concrete and steel containers above ground.

32.

true

33.

You can find substitutes for some hazard-ous household chemicals such as insect sprays.


Water Pollution and Solutions Guided Reading and StudyUse Target Reading Skills Possible questions and answers include the following:

Q. What are some household causes of water pollution?

A. Water and human wastes that are washed down sinks, toilets, and showers

Q. What is sediment?A. Rock and sand that has been eroded by

water1. a, c, d2. groundwater3. During the water cycle, water evaporates from oceans, lakes, and rivers. As it evaporates, any dissolved substances are left behind. The pure water vapor condenses into droplets that fall as precipitation.4. It is a period when less rain than normal falls in an area.5. pollutants6. Pollutants dissolve and move throughout a body of water.7. true8. a. agriculture, b. industry, c. households, d. mining

9. sewage10. a. animal wastes, b. fertilizer, c. pesticides11. sediments12. They cover up food sources, nesting sites, and eggs of organisms. They also block sun-light, which prevents algae and plants from growing. 13. Heated water can change the temperature of a body of water and kill organisms living there.14. proper sewage treatment; the reduction of pollutants; the effective cleanup of oil and gaso-line spills15. false16. b17. a18. They can recycle wastes to recover useful materials, and they can change their processes to produce less waste or less harmful waste.19. true20. When oil is present, the bacteria multiply quickly and feed on the oil.21. false22. Groundwater can be pumped to the sur-face, treated, and then returned underground.23. They can prevent water pollution by not pouring household chemicals, such as paint thinners and motor oil, down the drain.

Air Pollution and Solutions Guided Reading and StudyUse Target Reading Skills Possible causes include the following: Factory and power plant emissions that produce nitrogen oxides and sul-fur oxides when they burn coal and oil; gases emitted by automobiles and trucks; indoor air pollutants, such as toxic chemicals1. emissions2. The largest source is motor vehicles.3. One natural cause is an erupting volcano.4. photochemical smog5. false6. Ozone is the major chemical found in smog.7. It is a condition in which a layer of warm air prevents cooler rising air from escaping into higher parts of the atmosphere.8. Layer B is the warmest.9. A temperature inversion traps polluted air and holds it close to Earth’s surface.

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ANSWER KEYLand, Water, and Air Resourcesa

te

r,

an

d A

ir R

eso

urc

es

10. Smog can irritate people’s eyes and throats, cause breathing problems, and harm the body’s defenses against infection.11. acid rain12. bottom middle oval: Sulfur oxides; upper right oval: Nitric acid13. Acid rain kills many fish and their eggs, damages plants, destroys forests, reacts with stone and metal in buildings and statues, and makes automobiles rust more quickly.14. It is caused by dust, pet hair, tobacco smoke, glues, and cleaning supplies.15. a16. a, c, d17. emissions18. Scrubbers; Catalytic Converters19. Using less energy reduces the amount of fuels that are burned, and this reduces air pollution.


Global Changes in the Atmosphere Guided Reading and StudyUse Target Reading Skills Outlines should have Roman numerals followed by major headings and capital letters followed by minor headings.

I. The thinning of the ozone layerA. The source of ozoneB. The ozone holeC. What’s being done

II. Global climate changeA. The greenhouse effectB. Global warmingC. Possible consequencesD. The difficulty of predicting

climate change1. ozone layer2. true3. The major source is a group of gases called chlorofluorocarbons, or CFCs, that were used in many household products.4. Products include refrigerators, air condition-ers, fire extinguishers, and aerosol spray cans.5. It is the trapping of heat near Earth’s surface by gases in the atmosphere.

6.

7. The theory predicts that increasing carbon dioxide in the atmosphere will cause Earth’s average temperature to continue to rise.8. a, b, c

Key TermsfertilizerdevelopmentsubsoilleachategroundwaterpollutantpesticideerosionrecyclingbedrocktopsoilincinerationAnswer: reduce, reuse, recycle

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ANSWER KEY

Energy Resources


Fossil Fuels Guided Reading and Study


Example sentences include:An example of

energy transformation

is

combustion,

when a

fuel

is burned and chemi-cal energy is released.Oil, also called

petroleum,

is one of the

fossil

fuels,

which are all made up of energy-rich

hydrocarbons.

Many products that come from oil are produced in a

refinery,

where oil is heated and separated.

Petrochemicals,

which are also made from oil, are used to make medicines, plastics, paints, and cosmetics.

1.

fuel

2.

false

3.

combustion

4.

true

5.

a, c

6.

fossil fuels

7.

a. coal, b. oil, c. natural gas

8.

hydrocarbons

9.

bottom left oval: Oxygen; top right oval: Car-bon dioxide; middle right oval: Water

10.

coal

11.

false

12.

false

13.

c

14.

Coal mining can increase erosion, and run-off from mines can cause water pollution.

15.

petroleum

16.

b, c, d

17.

sound waves

18.

crude oil

19.

refinery

20.

petrochemicals

21.

a, d

22.

true

23.

false

24.

a, d


Renewable Sources of Energy Guided Reading and StudyUse Target Reading SkillsPossible questions and answers: How does the house capture solar energy? (Active solar collec-tors on the roof, large windows on south and west sides that act as passive solar collectors) What does the equipment that is on the roof and in the basement do? (Active solar cells on the roof gener-ate electricity that can be stored in the basement. Water heated in an active solar collector on the roof is stored in a tank in the basement and used to heat the

house.) What is the difference between active and passive solar heating systems? (Both con-vert sunlight into thermal energy, but only active systems use pumps and fans to distribute heat.)1. Solar energy is energy from the sun.2. a, c, d3. Rows of giant mirrors focus the sun’s rays to heat a tank of water. The water boils, making steam that can be used to generate electricity.4. true5. They are used to power calculators, lights, and other small devices.6. false7. Passive; Active8. Active solar heating systems use fans and pumps to distribute the heat.9. a. water, b. wind, c. biomass fuels, d. geothermal energy, e. hydrogen10. hydroelectric power11. false12. Most of the suitable rivers have already been dammed, and dams can have negative effects on the environment.13. b, d14. false15. biomass fuels16. a, b, d17. geothermal energy18. true

En

erg

y R

eso

urc

es

19.

20. It takes more energy to obtain pure hydro-gen than is produced by burning the hydrogen.

Cold water Steam

Magma

Bedrock

Power plant

Pump

Cooling tower

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ANSWER KEY

Energy Resources


Nuclear EnergyGuided Reading and Study


Similarities—both types of reactions release large amounts of energy and involve small losses of mass; differences—fission uses ura-nium and splits nuclei, fusion uses hydrogen and combines nuclei.

1.

nucleus

2.

Fission; Fusion

3.

true

4.

E = mc

2

5.

nuclear fission

6.

true

7.

The heat released from the reactions is used to change water into steam. The steam then turns the blades of a turbine to generate electricity.

8.

b

9.

a

10.

c

11.

d

12.

meltdown

13.

It is difficult because they remain dangerous for many thousands of years.

14.

nuclear fusion

15.

b, c

Energy Conservation Guided Reading and StudyUse Target Reading SkillsPossible AnswersWhat You Know1. I turn off lights to conserve energy.2. I walk instead of ride in a car when possible.

What You Learned1. One way to preserve our current energy resources is to increase efficiency.2. One method of increasing efficiency of heat-ing and cooling systems is to use insulation.3. Compact fluorescent bulbs use about one fourth as much energy as incandescent light bulbs.

1. One way is to increase the efficiency of our energy use. Another way is to conserve energy whenever possible.2. efficiency3. Most of the rest of the energy is “lost” to the surroundings, usually as heat.4. insulation5. Insulation traps air, and this layer of trapped air helps keep the building from losing or gain-ing heat from the outside.6. a


7. The air between the panes of glass acts as insulation to help prevent heat loss through the windows.8. false9. Engineers have designed better engines and tires.10. Communities can maintain public transit systems that provide an alternative to driving. They can also encourage carpooling, for exam-ple, by setting aside lanes for cars containing two or more people.11. energy conservation12. c, d

Key Termsfuelpetrochemicalpetroleumreactor vesselrefinerymeltdownefficiencyinsulationconservationhydroelectricgasoholhydrocarbonHidden Message: Fuel provides energy.

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ANSWER KEY

Stars, Galaxies, and the Universe

Telescopes Guided Reading and Study Use Target Reading Skills Check student defi-nitions for accuracy.

1. Electromagnetic radiation is energy that can travel through space in the form of waves.

2. visible light

3. wavelength

4. spectrum

5. red, orange, yellow, green, blue, and violet

6. It includes radio waves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.

7. They collect and focus electromagnetic radiation.

8. A convex lens is a piece of transparent glass, curved so that the middle is thicker than the edges.

9. a. Uses convex lenses to gather and focus light b. Uses a curved mirror to collect and focus light c. Has a curved, reflecting surface that focuses radio waves d. A radio telescope detects electromagnetic radiation that is not visible to humans. e. A radio telescope focuses radio waves the way refracting and reflecting tele-scopes focus visible light waves.

10. refracting telescope

11. reflecting telescopes

12. observatory

13. Earth’s atmosphere makes objects in space look blurry. The sky viewed from some moun-taintops is clearer and is not brightened by city lights.

14. Some telescopes in space can detect ultra-violet radiation, X-rays, and gamma rays that are blocked by Earth’s atmosphere. Others can detect visible light or infrared radiation that is partially interfered with by Earth’s atmosphere.

15. It makes such detailed images because it is above Earth’s atmosphere.

Characteristics of Stars Guided Reading and Study Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers.

1. constellations

2. a. color b. temperature c. size d. composi-tion e. brightness

3. Its color reveals its temperature.

What You Know

1. Stars are bright and hot.

2. Distances between stars are measured in light-years.

3. The sun is a yellow star.

What You Learned

1. Stars are classified based on color, tempera-ture, size, composition, and brightness.

2. Light travels through space a distance of 9.5 million million kilometers in one year.

3. The sun has a surface temperature of about 5,800˚ C.


4. d5. giant stars or supergiant stars6. true7. They can compare a star’s spectrum with

the known spectrums of different elements.8. A spectrograph breaks the light from an

object into colors and makes an image of the resulting spectrum.

9. about 73 percent hydrogen, 25 percent helium, and 2 percent other elements by mass10. brightness11. Rigel is very hot, so each square meter of its photosphere gives off a lot of light. Betelgeuse is a fairly cool star, so each square meter of its photosphere doesn’t give off much light.12. a. How far the star is from Earth b. How bright the star actually is13. a. The brightness of a star as seen from Earth b. The brightness a star would have if it were at a standard distance from Earth c. Star X has a greater apparent brightness than Star Y. d. You cannot compare the absolute brightness because you do not know how much farther Star Y is from Earth than Star X. Star Y may be brighter or not as bright as Star X if both are seen from the same distance.14. true15. a. The star’s apparent brightness b. The star’s distance from Earth16. false17. A light-year is the distance that light travels through space in one year.18. 9.5 million million19. false20. Parallax is the apparent change in position of an object when you look at it from different places.21. d22. sun23. Hertzsprung-Russell diagram

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ANSWER KEY

Stars, Galaxies, and the Universe


24. a. Surface temperature (˚C) or colorb. Absolute brightness

25. main sequence

26. a, c, d

Lives of StarsGuided Reading and Study Use Target Reading Skillsa. A star is born as fusion begins.b. The star begins to run out of fuel.c. The star becomes a red giant, then a white dwarf, and then a black dwarf.

1. true

2. nebula

3. protostar

4. A star is born when the contracting gas and dust from a nebula become so dense and hot that nuclear fusion starts.

5. a

6. false

7. e


8. d9. b10. a11. c12. a. Protostar b. White Dwarf c. Supernova d. Black Hole e. Stars that are the most massive become black holes. Stars that are less massive but still high-mass stars become neutron stars. f.They all start out as a part of nebulas that con-tract to form protostars. g. Stars with different masses reach different end stages. (Students may also name the end stages associated with stars of different masses.)13. The sun may have begun as a nebula that contained material from a supernova.14. They can detect X-rays coming from rotat-ing hot gas near a black hole. They can detect the presence of a black hole from the effect of its gravity on a nearby star.

Star Systems and Galaxies Guided Reading and Study Use Target Reading Skills Check student defi-nitions for accuracy.

1. They are groups of two or more stars.2. binary stars3. a4. eclipsing binary5. They observed the effects of the planet’s

gravity on the star.

6. Any small planets would be hard to detect because their gravitational effect on their star would be quite small.

7. open cluster8. globular cluster9. billions

10. a11. c12. b13. b, c14. quasar15. Milky Way16. The Milky Way is usually thought of as a standard spiral galaxy. However, some evidence suggests that the Milky Way may be a barred-spiral galaxy instead.17. The numbers they use are often very large or very small.18. 3.8 × 10 13 kilometers 19. The Local Group is a cluster of about 50 gal-axies to which the Milky Way belongs.20. about 1010 light-years, or 1026 meters

�

The Expanding Universe Guided Reading and Study Use Target Reading Skills Moving Galaxies: All galaxies are moving away from us and from each other. Cosmic Background Radiation: This glow comes from thermal energy left over from the big bang explosion.

1. big bang2. It occurred billions of years ago.3. true4. The galaxies in the universe, like the raisins

in the rising dough, are moving away from one other. In the universe, it is space that is expand-ing, like the dough between the raisins.

5. cosmic background radiation6. They know approximately how fast the uni-

verse is expanding now.7. five billion years ago8. A large cloud of gas and dust collapsed.

Gravity pulled the cloud together and as it shrank, it spun faster and faster, forming a rotat-ing disk. Gravity pulled most of the gas into the center, where the gas became hot and dense enough for nuclear fusion to begin.

9. Planetesimals collided and grew larger by sticking together, eventually combining to form the planets.

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ANSWER KEYStars, Galaxies, and the Universe


10. a. The universe will continue to expand as it is doing now. Eventually all the stars will run out of fuel. b. The force of gravity will begin to pull the galaxies back together. The result will be a reverse big bang. All of the matter in the universe will eventually be crushed into an enormous black hole.11. A is more likely because astronomers have observed that the expansion of the universe appears to be accelerating. They infer that a force called dark energy is causing this acceleration.

Use Key Terms1. protostar2. black hole3. spectrograph4. universe5. neutron star6. big bang7. constellation8. supernova9. spiral galaxy

10. observatory11. radio telescope12. parallax13. quasarHidden Message: The sun is a star.


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Guided Reading and Study Workbooksciencewithmshawkins.weebly.com/uploads/9/2/4/3/9243701/... · Guided Reading and Study Workbook Answer Key. Cover photographs courtesy of iStockPhoto