Chapter 19: Respiration and Excretion - mrwrightsclass.netmrwrightsclass.net/resources/old-7th-grade-text/chap19.pdf · The Excretory System 2 Sessions 1 Block 1. ... one positive

518B

Chapter Review, pp. 37–38Assessment, pp. 73–76Performance Assessment in the Science

Classroom (PASC)MindJogger VideoquizAlternate Assessment in the Science

ClassroomPerformance Assessment, p. 19Chapter Review SoftwareComputer Test Bank

Chapter Organizer

Standards Reproducible Resources Technology

National State/Local

National ContentStandards: A1, A2,B1, C1, C3, E1, F1,F3, F4, F5, G1, G3

National ContentStandards: UCP1,UCP4, A1, A2, C1

Activity Worksheets, pp. 103–104, 107 Critical Thinking/Problem Solving, p. 19 Enrichment, p. 53 Laboratory Manual, pp. 111–114 Laboratory Manual, pp. 115–116 Reinforcement, p. 53 Study Guide, pp. 73-74

Activity Worksheets, pp. 105–106, 108 Enrichment, p. 54 Multicultural Connections, pp. 37–38 Reinforcement, p. 54Study Guide, pp. 75–76

Section Focus Transparency 53 Teaching Transparency 37 Science Integration Transparency 19Glencoe Science VoyagesInteractive CD-ROMNational Geographic Society: STVInternet Connection, p. 527Internet Connection, p. 534

Section Focus Transparency 54 Teaching Transparency 38

Assessment Resources

Level 1 activities should be appropriate for students with learning difficulties.

Level 2 activities should be within the ability range of all students.

Level 3 activities are designed for above-average students.

ELL activities should be within the ability range of English Language Learners.

Cooperative Learning activities are designed for small group work.

These strategies represent student products that can be placed into a best-work portfolio.

Multiple Learning Styles logos, as described on page 63T, are used throughoutto indicate strategies that address different learning styles.

P

COOP LEARN

ELL

L3

L2

L1

The following designations will help you decide which activities are appropriate for your students.

Key to Teaching Strategies

English and Spanish audiocassettes areavailable for use with each section.

Test Practice Workbooks are available foruse with each chapter.

California ScienceContent Standards:5a, 5b, 7a, 7b, 7c,7e

California ScienceContent Standards:5a, 5b, 7b, 7c, 7e

Chapter 19

518A CHAPTER 19 RESPIRATION AND EXCRETION

Section Objectives Activities/Features

Activity MaterialsExplore Activities MiniLabs

Chapter 19 Respiration and Excretion

Chapter Opener

19-1The Respiratory System

4 Sessions2 Blocks

19-2The Excretory System

2 Sessions1 Block

1. State three functions of the respiratorysystem.

2. Explain how oxygen and carbon dioxide areexchanged in the lungs and in tissues.

3. Trace the pathway of air in and out of thelungs.

4. Name three effects of smoking on therespiratory system.

5. Distinguish between the excretory andurinary systems.

6. Describe how your kidneys work.7. Explain what happens when urinary organs

don’t work.

Explore Activity: Observe Breathing Rate, p. 519

Using Math, p. 522MiniLab: Measuring Surface Area, p. 524Physics Integration, p. 525Using Math, p. 528Skill Builder: Making Models, p. 529Science Journal, p. 529Activity 19-1: The Effects of Exercise on

Respiration, pp. 530–531How It Works: Scuba, p. 532

MiniLab: Modeling Kidney Function, p. 535Problem Solving: Analyzing Water Gain and

Loss, p. 536Physics Integration, p. 537Skill Builder: Concept Mapping, p. 538Using Math, p. 538Activity 19-2: Kidney Structure, p. 539

p. 519stopwatch or timer withsecond hand

pp. 530–531timer, drinking straws, 200 mL bromothymol bluesolution, 2 12-ounce glass cups, metric measuring cup

p. 539large animal kidney, scalpel, hand lens

p. 524tape, paper, scissors

p. 535dirt, cup, funnel, filter paper, water

The number of recommended single-period sessions The number of recommended blocksOne session and one-half block are allowed for chapter review and assessment.

Need Materials? Contact Science Kit at 1-800-828-7777 or at www.sciencekit.com on the Internet. For alternate materials, see the activity on the listed page.

http://www.sciencekit.com

Critical Thinking/Problem Solving

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. 21

NAME DATE CLASS

Chapter 21

CRITICAL THINKINGRespiration and Excretion

Most people are aware that cigarette smok-ing has been linked to lung cancer inhumans. But do you know that the U.S.Department of Health considers cigarettesmoking to be the principal cause of unneces-sary, preventable illness and early death?Illnesses linked to cigarette smoking alsoinclude mouth cancer, heart disease, and gumdisease. And smokers are ten times morelikely than nonsmokers to develop emphyse-ma or bronchitis.

Recently, the National Cancer Institutefound a link between cigarette smoking andnutrition. They discovered that smokers tendto eat less fruits, vegetables, fish, and poultrythan nonsmokers. These foods are healthy,contain generous amounts of vitamins A andC, and are thought to be instrumental in theprevention of cancer.

Another study showed that smokingincreases the risk of death in diabetics. The

risk of death was especially high for womendiabetics who smoke. Diabetics normallyhave a high rate of heart disease. Since smok-ing accelerates heart disease, people with dia-betes should avoid smoking.

Doctors who perform plastic surgery havefound that patients who smoke suffer moreskin loss after surgery than nonsmokers. Thenicotine in cigarettes causes the blood vesselsof smokers to constrict. The lack of blood cir-culating in the affected skin doesn’t allow itto heal properly. A recent study suggestsplastic surgery patients who smoke shouldquit smoking for at least several weeks beforeand after their surgery. This may prove help-ful in the healing process.

There are lots of health risks linked to ciga-rette smoking. In fact, smoking doesn’t haveone positive effect on human health. Andscientists are continuing to find more nega-tive effects of cigarette smoking.

Applying Critical Thinking Skills1. Imagine that your friend has been experimenting with cigarette smoking. What reasons would

you give your friend to stop smoking?

2. What type of results from skin graft surgery to repair burned skin would you expect in apatient who is a nonsmoker compared to a patient who smokes?

3. With all the health hazards connected with cigarette smoking, why do you suppose people continue to smoke?

Additional Hazards of Cigarette Smoking

L2

Accessibility

Resource Manager

Hands-on Activities

Lab ManualActivity Worksheets


NAME DATE CLASS

Chapter 21

ACTIVITY 21-1The Effects of Exercise on Respiration

Lab Preview1. What is the function of the respiratory system?

The respiratory system delivers oxygen to the blood and removes carbon dioxide

waste from the blood.

2. What is breathing?

Breathing is the process whereby fresh air moves into the lungs and stale air moves

out of the lungs, that is, the process of inhaling and exhaling.

Breathing rate increases with an increase in physical activity. A bro-mothymol blue solution changes color when carbon dioxide is bubbledinto it. Can you predict whether there will be a difference in the time ittakes for the solution to change color before and after exercise?

Design Your Own Experiment

Recognize the ProblemHow will an increase in physical activity

affect the amount of carbon dioxide exhaled?

Form a HypothesisState a hypothesis about how exercise will

affect the amount of carbon dioxide exhaledby the lungs.

Goals• Observe the effects of the amount of carbon

dioxide on the bromothymol blue solution.• Design an experiment that tests the effects

of a variable, such as the amount of carbondioxide exhaled before and after exercise,on the rate at which the solution changescolor.

Possible Materials• clock or watch with second hand• drinking straws• bromothymol blue solution (200 mL)• glass cups (12 oz.) (2)

*beakers (400-mL) (2)• metric measuring cup

*graduated cylinder*alternate materials

Safety Precautions Protect clothing from the solution. Wash

hands after using the solution. CAUTION: Donot inhale the solution through the straw.

L2Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. 117

NAME DATE CLASS

Chapter 21

LABORATORY MANUALHow does breathing occur? 41

If you have ever tried to hold your breath, you know that breathing is automatic.Breathing is moving air into and out of the lungs. Taking in air is called inhalation.Letting out air is called exhalation. Your ribs and chest help with breathing. A musclecalled the diaphragm also helps by contracting as you inhale and relaxing as youexhale.

StrategyYou will compare a model to a human chest.You will use the model to show how the diaphragm and chest help inhalation and exhalation.

Materials model of the human chest

ProcedureCAUTION: Use care when handling sharp objects.

Part A Model Parts and How They Work1. Obtain a model of the human chest from your teacher.

2. Using FIGURE 1 as a reference, push up gently on the rubber sheet and note the waterlevel change in the tube. Record the water level changes for both sides of the tube inTable 1.

3. Pull down gently on the rubber sheet and note the water level change in the tube. Recordyour observations in Table 1.

Part B Comparing Your Model with the Human ChestCompare FIGURES 1 and 2. Match the parts of the model (FIGURE 1) with the parts of the humanchest (FIGURE 2) in Table 2.

See FIGURE 1 for details onbuilding the model.

For plastic dome, use a 3-L plastic soft drink bottle. Rubbersheets are available from local dentist or supply house (called rubber dam).

FIGURE 2 The human chestFIGURE 1 Model of the human chest

L2

Hands-on Activities

Chapter Review

41

Part A. Vocabulary ReviewUnscramble the letters to form the correct word for each definition.

______________________ 1. anhxypr tubelike passageway for both food and air

______________________ 2. ryalxn structure to which vocal cords are attached

______________________ 3. erhcaat tube with cartilage, mucous membranes, and cilia

______________________ 4. hobcirn branches of the trachea

______________________ 5. iavello clusters of thin-walled air sacks in the lungs

______________________ 6. pridamagh muscle under lungs that helps air move in and out

______________________ 7. etreurs tubes that lead from each kidney to the bladder

______________________ 8. rarnuyi semsty system made up of excretory organs

______________________ 9. snedyik major organs of urinary system

______________________10. sponnher filtering units of the kidneys

______________________11. neiru waste fluid that is excreted from the body

______________________12. derdabl organ that holds urine until it is excreted

______________________13. ratruhe tube that leads to the outside of the body

Complete the following lists.

14. List four diseases or disorders of the respiratory system.

a. _____________________________________

b. _____________________________________

c. _____________________________________

d. _____________________________________

15. List the three major excretory organs.

a. _____________________________________

b. _____________________________________

c. _____________________________________

NAME DATE CLASS

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Respiration and Excretion

Chapter 21

CHAPTER REVIEW

3/21:1

3/21:1

3/21:1

3/21:1

3/21:1

3/21:1

6/21:2

5/21:2

6/21:2

6/21:2

6/21:2

pharynx

larynx

trachea

bronchi

alveoli

diaphragm

ureters

urinary system

kidneys

nephrons

urine

bladder

urethra

emphysema

4/21:1

chronic bronchitis

asthma

6/21:2

6/21:2

lung cancer

lungs

skin

kidneys

5/21:2

L2

Performance Assessment


Maintaining good health seems to require a combination of good food, exercise, rest, and a posi-tive attitude about life. With so much emphasis on exercise, you might think that only a fast runaround the block will burn calories. But calories are “burned” because the cells in your body arealways undergoing respiration. While running increases the rate of respiration, it still goes oneven when you sleep. Look at the table and answer the questions below.

1. How many calories are used by the 73 kg person during seven hours of sleep? How many hours ofsleep would it take the person who weighs 63 kg to use up the same number of calories?

2. Calorie usage drops significantly for all groups during sleep. How does activity during sleep differfrom an activity such as walking? What does this tell you about the rate of respiration during anyday?

3. What activity should most people engage in to burn the greatest number of calories with the leastamount of stress?

Mass of Person

NAME DATE CLASS

Chapter 21

SKILL ASSESSMENT Burning Those Calories

Calories Used in One Hour

Type of Activity

Sleeping

Sitting

Eating

Standing

Walking

Playing tennis

Bicycling fast

Running

54 kg

48

72

84

96

180

380

500

700

63 kg

56

84

98

112

210

420

600

850

73 kg

64

96

112

123

240

460

700

1000

L2

Assessment Extending ContentExtending Content

Accessibility

Multicultural ConnectionsTest Practice WorkbookAssessment


I. Testing ConceptsMatch the description in the first column with the item in the second column by writing the correct letter in the spaceprovided. Some items in the second column may not be used.

_____ 1. structure to which vocal cords are attached 2/21:1

_____ 2. tube with cartilage, mucous membranes, and cilia 2/21:1

_____ 3. branches of the trachea 2/21:1

_____ 4. clusters of thin-walled air sacs 2/21:1

_____ 5. muscle beneath lungs that helps air move in and out 3/21:1

_____ 6. disease resulting in the alveoli losing their ability to expand and contract 4/21:1

_____ 7. tubes that lead from each kidney to the bladder 6/21:2

_____ 8. major organs of urinary system 5/21:2

_____ 9. filtering units of the kidneys 6/21:2

_____ 10. organ that holds urine until it leaves the body 6/21:2

For each of the following, write the letter of the term or phrase that best completes each sentence.

_____ 11. When you breathe, your lungs take in oxygen and remove ________ . 1/21:1a. air b. carbon dioxide c. nitrogen d. nitrogen dioxide

_____ 12. Cell respiration involves supplying your body’s cells with ________ . 1/21:1a. oxygen b. blood c. bone marrow d. enzymes

_____ 13. People whose ________ don’t work may have to undergo dialysis. 7/21:2a. alveoli b. bladders c. kidneys d. lungs

_____ 14. The ________ is a tubelike passageway for both food and air. 2/21:1a. epiglottis b. larynx c. pharynx d. trachea

_____ 15. The ________ prevents food or liquid from entering your trachea. 2/21:1a. alveoli b. bronchi c. epiglottis d. larynx

_____ 16. Within the lungs, the exchange of oxygen and carbon dioxide occurs between the________ and the capillaries. 3/21:1a. trachea b. bronchi c. alveoli d. diaphragm

_____ 17. When urinary organs don’t work, all of the following occur EXCEPT ________ .7/21:2a. swelling c. accumulation of wastesb. homeostasis d. salt imbalance

_____ 18. A disorder of the lungs called ______ is often an allergic reaction. 4/21:1a. asthma b. chronic bronchitis c. emphysema d. lung cancer

NAME DATE CLASS

Chapter 21

CHAPTER TEST Respiration and Excretion

i

k

d

a

f

g

l

h

j

c

a. alveoli

b. asthma

c. bladder

d. bronchi

e. chronic bronchitis

f. diaphragm

g. emphysema

h. kidneys

i. larynx

j. nephrons

k. trachea

l. ureters

m. urethra

b

a

c

c

c

c

b

a

L2 L2Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

41

To a patient in need of a kidney, a surgicaltransplant is literally a lifesaver. But if thepatient’s body rejects the organ, death is quitepossible.

Fortunately for thousands of people who gettransplants worldwide, Samuel Kountz, M.D.,made a valuable discovery. In late 1963 he dis-covered that a drug called methylpred-nisolone helped to reverse the rejection of atransplanted kidney. He also developed amethod by which the dosage of the drugcould be checked, so that the person gettingthe transplant would not die of a drug overdose.

The idea is simple: When an organ is trans-planted from one person to another, thepatient’s body tends to treat the grafted or“donated” organ as an invader. The bodystrives to reject the organ—usually bydecreasing the blood supply until the organdies for lack of oxygen. Dr. Kountz discoveredthat methylprednisolone stopped the body’srejection mechanism and brought back anadequate supply of blood. If just the rightdosage were used, the chance of a kidney’sacceptance improved greatly.

Donor Card PioneerDr. Kountz’s research made headlines

around the world. But he did not merely restin his glory. Instead he used his fame toincrease public awareness of the need fororgan donors. He once performed a kidneytransplant on live television, inspiring approx-imately 20 000 people to offer their kidneys topatients who needed them. And with the sup-port of the National Kidney Foundation, heproposed that citizens carry organ donorcards. In 1965, he said, “We really need 100million persons carrying cards to assure thatwe will get the kidneys we need.”

To help increase the likelihood that a donatedkidney would be accepted by the patient, Dr.Kountz performed groundbreaking work in“tissue typing,” a process by which a donorcould be carefully “matched” to a patient forthe greatest likelihood of success. Dr. Kountzalso worked with a team of other researchersto develop a machine that preserved kidneysfor up to 50 hours after removal from adonor’s body. This machine, which Kountznamed the Belzer Kidney Profusion Machine

in honor of his medical partner, is now stan-dard equipment in hospitals and research cen-ters around the world.

Global Impact, Local ValueWhile Kountz was known worldwide for his

medical “firsts” (in 1961 he and his mentor,Dr. Roy Cohn, performed the first successfulkidney transplant between humans who werenot identical twins; in 1966 he performed thefirst successful kidney transplant in theMiddle East), he was also known among hiscolleagues as a particularly warm and funnyman. He often said that he performed kidneytransplants so that “a person can be kept aliveat 20 to die of something else at 65.” He alsotreated each patient as a human being, notmerely a medical “case.”

Dr. Kountz’s passion for service took himfrom the University of California, SanFrancisco, to Downstate Medical Center inBrooklyn, New York, where in 1972 he accept-ed the job of chairperson in the department ofsurgery. (He also served as chief of surgery atKings County Hospital.) Kountz choseDownstate because it was in a predominantly

Chapter 21

MULTICULTURAL CONNECTIONSThe Search forCompatible Kidneys

NAME DATE CLASS

L2

518D

Spanish Resources

L2

Test Practice Workbook

L2

Meeting Different Ability Levels

Transparencies

Chapter 19 Chapter 19 Respiration and Excretion

Enrichment WorksheetsReinforcementStudy Guide

for Content Mastery

Cop

yrig

ht ©

Gle

ncoe

/M

cGra

w-H

ill, a

div

isio

n of

The

McG

raw

-Hill

Com

pani

es, I

nc.

81

Name Date

CHAPTER 21 Study Guide for Content Mastery

Overview Respiration and ExcretionDirections: Use the following terms to label the diagram below:

alveoli bronchi diaphragm pharynxlungs nasal cavity trachea

Directions: Write the name of the structure indicated on the lines below.

1. warms and moistens air; filters dust particles

2. transports air to the lungs

3. passageway for air and food

4. oxygen passes from them into capillaries

5. organs made up of alveoli

6. sheet of muscle across the bottom of the chest cavity

7. division of the tracheabronchi

diaphragm

lungs

alveoli

pharynx

trachea

nasal cavity

2. trachea

1. nasal cavity

5. pharynx

6. bronchi

7. alveoli

3. lungs

4. diaphragm

BASIC

1.

3.

4.

6.

7.

2.

nasal cavity

pharynx

trachea

bronchi

5. alveoli

lung

diaphragm


NAME DATE CLASS

Chapter 21

REINFORCEMENT The Respiratory System

Use with Section 1

Label the parts of the respiratory system shown in the diagram below.

In the space provided below, write the name of the structure indicated.

__________________ 1. warms and moistens air; filters dust particles

__________________ 2. transports air to the lungs

__________________ 3. prevents food from entering the trachea

__________________ 4. oxygen passes into the capillaries

__________________ 5. organs made up of masses of alveoli

__________________ 6. a sheet of muscle across the bottom of the chest cavity

__________________ 7. a division of the trachea

Label each statement below as a description of either inhalation or exhalation. Write the word inhale or exhale in thespace provided below.

__________________ 8. The diaphragm contracts and moves downward.

__________________ 9. Air pressure in the chest cavity increases.

__________________ 10. The gases inside the lungs are pushed out through air passages.

__________________ 11. Air pressure in the chest cavity decreases.

__________________ 12. The volume of the chest cavity increases.

1.

3.

4.

6.

7.

2.

5.

nasal cavity

trachea

epiglottis

alveoli

lungs

diaphragm

bronchus

inhale

exhale

exhale

inhale

inhale

AT LEVELCopyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. 57

The Respiratory System

Use with Section 1

NAME DATE CLASS

Chapter 21

ENRICHMENT

ExhalingHow much air do you exhale in one breath? One way to find out might be to blow up a balloon

and see how big it gets. A better way to measure how much air you exhale in a single breath is tosee how much water is displaced by the air you exhale. Try the following activity.

Materials3.79-liter plastic milk jug0.5-liter measuring cupmarking penflexible plastic tubing, about 60 cmsink with stopper

Procedure1. Use the measuring cup and water to fill the milk jug. After adding each 0.5 liter of water, mark

the volume on the side of the jug.2. Fill the jug with water to overflowing. Push the stopper in the sink and fill it with 10 cm of

water.3. Cover the opening of the jug with your hand and turn the filled jug upside-down over the

sink. Put the jug in the sink with the opening under water. Have someone hold the jug for you.4. Push one end of the plastic tubing through the opening of the jug, take a deep breath and blow

into the other end of the tube.5. Use the markings on the side of the jug to estimate the volume of water remaining in the jug.

ObservationsWhat happened to the water in the jug? ___________________________________________________

the tube.

Compare how much air you typically exhale in one breath to that of others. Include people of different ages, sizes,sexes, and activity levels. Use a different piece of clean tubing for each person. Develop a questionnaire for your testsubjects. It should include some of the following questions:

1. Are they in good health? Any chronic bronchitis, asthma, emphysema, or other lung ailments?

2. Have they ever smoked? Does anyone smoke at home?3. Do they live in a rural or urban setting?4. Do they exercise on a regular basis?Use the answers to the questions to write a conclusion.

Conclusion

It was displaced by the air entering through

CHALLENGE

Meeting Different Ability Levels

Section Focus Transparencies

Teaching TransparenciesScience Integration

Transparencies

Copyright©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. 53

53

WATER WORLDScuba diving and snorkeling are activities that require special equipment

that allow you to breathe while your body is in the water. This equipment isneeded because unlike fish, which are adapted to breathe in oxygen dis-solved in water, people breathe in oxygen from the air.

1. What special equipment is required for scuba diving? Why is this equip-ment important?

2. How do divers and fish differ in the way they get oxygen?

SECTION FOCUS TRANSPARENCYSection 19-1

L2Copyright©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. 54

54

REMOVING LIQUID WASTESDo you perspire heavily when you exercise? Perspiration is a liquid waste

given off by the body. It contains mostly water and dissolved salts.

1. In addition to eliminating waste materials, in what other way is perspir-ing helpful to the body?

2. Why is it important to drink plenty of fluids when you are involved inactivities that cause you to perspire heavily?

3. What other body system is involved in the removal of liquid wastes?


L2

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

19SCIENCE INTEGRATION TRANSPARENCY

Boyle’s Law and Breathing

Low Air Pressure High Air Pressure

Boyle’s Law At the same temperature, the pressure of quantity of gas will increase as the volume is decreased, according to a mathematical proportion:

original pressure ×× original volume = increased pressure ×× decreased volume

Air AirInhale Exhale

Low Air Pressure High Air Pressure

Volume decreased(Air would normally escape)

Original volume

Boyle’s Law At the same temperature, the pressure of quantity of gas will increase as the volume is decreased, according to a mathematical proportion:

original pressure ×× original volume = increased pressure ×× decreased volume

Ribcage expands

Diaphragm contracts

Ribcage rests

Diaphragm relaxesin upward position

Air AirInhale Exhale

L2Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

37. RESPIRATORY SYSTEM

Alveoli

Capillaries

To the heart

Vein

Alveoli

Artery

From the heartBronchiole

L2Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

38. URINARY SYSTEM

L2

Transparencies

This is a representation of key blackline masters available in the Teacher Classroom Resources.See Resource Manager boxes within the chapter for additional information.

L1 L2 L3

518C CHAPTER 19 RESPIRATION AND EXCRETION

Urine (Section 19-2)

The urea and uric acidare wastes from themetabolism of pro-teins. The straw colorof fresh urine is due toa pigment called uro-chrome. The averagepH of urine is approxi-mately 6.0, making it slightly acidic.

The urinary system also functions in main-taining the homeostasis of body fluids and elec-trolytes and keeps in proper balance the levelsof acids and bases. All of this provides for theuniform composition of the blood components.

Urinary Tract Infections (Section 19-2)

Urinary tract infections are common, secondonly to respiratory infections. Normally, urineis sterile. An infection occurs when microbes—usually bacteria from the digestive tract—ad-here to the opening of the urethra and begin tomultiply. Most infections can be traced to onetype of colon bacteria, Escherichia coli (E. coli).Often the bacteria move from the urethra to thebladder causing a bladder infection. Urinary in-fections are rarely seen in boys and young men.The rate of urinary infections in females gradu-ally increases with age. Such infections aretreated with specific antibacterial drugs.

reported in the media when pollen is abundant.The worst allergens include wind-pollinatedtrees, grasses, and ragweed, but not hay.

Pneumonia is the term used to describe anycondition that results in alveoli filling up withfluid. It can be caused by a number of differentfactors, including chemicals, bacteria, viruses, orfungi. The usual cause is Streptococcus bacterium.Pneumonia most readily attacks people who arealready weakened by illness or who have dam-aged lungs. Blood infections, chronic alcoholism,inhalation of fluids into the lungs, or even pro-longed bed rest can predispose a person to infec-tion of the lungs by microorganisms.

Your Urinary System (Section 19-2)

The metabolic processes of the body producewaste products. The respiratory system rids thebody of carbon dioxide. The digestive systemeliminates solid wastes. The urinary system re-moves a variety of salts and nitrogenous wastesfrom the blood and lymph systems.

The major organs of the urinary system are apair of bean-shaped structures called kidneys,each of which is approximately 10 cm long and5 cm wide. They weigh about 170 g each. Thefunctioning unit of the kidney is the nephron.All of the blood in the body flows through thekidneys in approximately 5 minutes.

518F

For current events or science in the news,access the Glencoe Science Web Site atwww.glencoe.com/sec/science/ca

ontent Background

ontent Background

CC

Teacher to TeacherTeacher to Teacher“To prepare for labs, I have my students write the procedure on

their papers as I write it using the overhead projector. During

labs, students can look at the screen from their lab stations if

they cannot read their handwriting or want to check that their

procedure is correct.”

Catherine Walker, Teacher

Martin Middle School

Raleigh, NC

Chapter 19

518E CHAPTER 19 RESPIRATION AND EXCRETION

Functions of the Respiratory System (Section 19-1)

In order to function, cells need nutrients. Thesenutrients must be oxidized in order to releaseenergy. The process of obtaining energy fromnutrients is called cellular respiration. The mostcommonly used carbohydrate used in respira-tion is glucose. The oxidation of glucose pro-duces water, carbon dioxide, and energy.

C6H12O6 � 6O2 → 6H2O � 6CO2 � energy

Obtaining oxygen and the removing of car-bon dioxide are the major functions of the res-piratory system. There are two successivephases of the functioning of the system—breathing and transporting gases.

In order to effectively exchange the gases in-volved in respiration, a large surface area is re-quired. It is estimated that the surface area ofthe alveoli of an adult is nearly 100 m2. Themovement of air in and out of the lungs is pos-sible due to three factors—the ability of thethoracic cavity to change size, the elasticity ofthe lung tissue, and the differential in pressurebetween the lungs and chest.

Lungs (Section 19-1)

Lungs are pink at birth, but as a person ages,they become gray and mottled from tiny parti-cles breathed in with the air. Usually, peoplewho live in cities and industrial areas havedarker lungs than those who live in the country.

In the adult human, the left lung is dividedinto two sections, or lobes—the superior andthe inferior. The right lung is somewhat largerthan the left lung and is divided into threelobes—the superior, middle, and inferior. Thetwo lungs are separated by a structure, whichcontains the heart, trachea, esophagus, andblood vessels.

There are 300 million to 400 million alveoli ineach lung. The air sacs of both lungs have a totalsurface area of about 93 m2, nearly 50 times thetotal surface area of the skin.

Hay Fever and Pneumonia (Section 19-1)

The symptoms of hay fever include abundanttears and a runny nose. It is a common allergicreaction. So many people are affected thatpollen counts of the atmosphere are regularly

Products Available from GlencoeTo order the following products for use with this chap-ter, call Glencoe at 1-800-334-7344:

CD-ROMNGS PictureShow: Human Body 2Curriculum KitGeoKit: Human Body 1Transparency SetNGS PicturePack: Human Body 2VideodiscSTV: Human Body

Products Available from NationalGeographic SocietyTo order the following products for use with this chapter,call National Geographic Society at 1-800-368-2728:

VideosCirculatory and Respiratory Systems (The HumanBody Series)Incredible Human Machine

Teacher’s Corner

Chapter 19 Respiration and Excretion

CD-ROMGlencoe Science Voyages Interactive CD-ROM

Chapter SummariesUse the Chapter Summary to introduce, teach,or review chapter material.

Helping You Prepare

http://www.glencoe.com/sec/science/ca

Explore Activity

Have you ever played basketball or run sohard that it felt like your lungs would

burst? How long did it take your breathingrate to return to normal? You can live morethan a week without food. Youmight live several days withoutwater. But, you can live only sev-eral minutes without oxygen. Yourbody has the ability to store foodand water. It cannot store muchoxygen. It needs a continuous sup-ply to keep your body cells function-ing. Sometimes, your body needs alot of oxygen. In the following activ-ity, find out about one factor that canchange your breathing rate.

Observe Breathing Rate

In your Science Journal,record your breathing ratebefore and after physicalactivity. Also, write downhow long it took for yourbreathing rate to return tonormal. Describe anychanges you observed.Write an explanation ofhow breathing rateappears to be related tophysical activity.

519

1. Put your hand on your chest. Takea deep breath. Feel your chestmove up and down slightly. Noticehow your rib cage moves out andupward when you inhale.

2. Count your breathing rate for 15 s.Multiply this number by four to fig-ure your breathing rate for oneminute. Repeat this activity and cal-culate your average breathing rate.

3. Jog in place for one minute andcount your breathing rate again.

4. How long does it take for yourbreathing rate to return to normal?

519

Explore ActivityPurpose

Kinesthetic Use the Ex-plore Activity to dis-

cover how the respiratorysystem responds to physicalactivity.

Preparation

Check with the school nurseto determine whether anystudent should not jog or en-gage in activities that stressthe heart and respiratorysystem.

Materialswatch or clock with a secondhand or a timer that canmeasure seconds

Teaching Strategies• Any student not able to

participate in the physicalpart of this activity can bedesignated as a timekeeperor recorder.

• Review the reason for mul-tiplying by four to obtainthe pulse rate for oneminute.

S t u d e n t sshould ob-serve that

breathing rates increasedafter physical activities. An-swers will vary on the lengthof time it takes for breathingrates to return to normalrates due to differences inphysiology and fitness ofstudents.

Performance Have studentsdesign another activity thatwill result in an increase inbreathing rate. Do the activ-ity and gather the data.Graph the results. Use Per-formance Assessment in theScience Classroom, p. 25.

COOP LEARNELLL2

AssessmentPortfolioRefer to p. 541 for suggested items that stu-dents might select for their portfolios.

Performance AssessmentSee p. 541 for additional Performance As-sessment options.Skill Builder, p. 538MiniLab, pp. 524, 535Activity 19-1, pp. 530–531; 19-2, p. 539

Content AssessmentSection Assessment, pp. 529, 538Chapter Assessment, pp. 542–543Proficiency Prep, pp. 528, 538

Assessment Planner

CHAPTER 19Respiration

and ExcretionRespiration

and Excretion

Chapter Preview

Section 19-1The RespiratorySystem

Section 19-2The ExcretorySystem

Skills Preview

Skill Builder• Sequence

• Map Concepts

Activities• Design an Experiment

• Observe and Infer

MiniLabs• Measure

• Model

Respirationand ExcretionRespirationand Excretion

✔Reading Check

19

As you read this chapter,

look for clues that can help

you understand unfamiliar

terms. These clues can include

nearby words and sentences,

as well as illustrations.

C H A P T E R

518

518 CHAPTER 19 RESPIRATION AND EXCRETION

CHAPTER OVERVIEWSection 19-1 This sectiondetails the basic anatomy andphysiology of the respiratorysystem. The mechanics ofbreathing and a descriptionof respiratory diseases anddisorders are included.Section 19-2 The organs ofthe urinary system and otherexcretory organs are intro-duced. Their role in maintain-ing homeostasis is explained.

Chapter Vocabularypharynx asthmalarynx urinary systemtrachea kidneybronchi nephronalveoli urinediaphragm ureterchronic bladderbronchitis urethra

emphysema

Theme ConnectionEnergy Energy transforma-tion is a central theme in thistext. Cells require oxygen inorder to utilize nutrients andthereby provide the energyfor all cellular activities.Chemical energy is trans-formed into thermal and me-chanical energy.

If time does not permit

teaching the entire chap-

ter, use Reviewing Main

Ideas on pp. 540–541.

OUT OF

TIME?

MultipleLearning

Styles

Look for the following logos for strategies that emphasize different learning modalities.

Linguistic Activity, pp. 526, 528;Preview, p. 540Logical-Mathematical Activity, pp. 530–531; Enrichment, p. 536Visual-Spatial Quick Demo, pp. 521,537; MiniLab, p. 524; Multiple Learn-

ing Styles, p. 527; Enrichment, p. 534;Reteach, pp. 537, 540; Assessment, p. 538;Activity, p. 539

Auditory-Musical Inclusion Strate-gies, p. 521; Across the Curriculum,

p. 523; Out of Time, p. 540Kinesthetic Explore Activity, p. 519;Activity, p. 523; MiniLab, p. 535Interpersonal Discussion, p. 525; Enrichment, p. 537; Review, p. 540

C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy

BreathingCirculation

Carbon dioxideremoved fromcells to lungs

Carbon dioxideexhaled

Carbon dioxidewaste expelled

(Glucose) + (Oxygen) → (Carbon dioxide) + (Water) + (Energy)

Respiration

(exhale)

19 1 THE RESPIRATORY SYSTEM 521

your cells from digested food. Now, oxygen is used in a seriesof chemical reactions to release the energy in glucose. Thesereactions, shown in the equation in Figure 19-1, are called res-piration and occur in the mitochondria of cells. Carbon diox-ide and water molecules are waste products of respiration.These molecules are carried in your blood to your lungs. Whenyou exhale, you get rid of respiration’s waste product.

Figure 19-2 shows a place where there is decreased airpressure. The air is less dense at extreme heights, so there arefewer oxygen molecules in every breath you take. Whywould it be harder to breathe on top of mountains?

✔

Figure 19-2 Mount Everest is the highest place on Earth.Mountain climbers experienceheadaches, nausea, and shortnessof breath while ascending to the topof high mountains.

✔Reading Check

What is the difference

between breathing

and respiration?

19-1 YOUR RESPIRATORY SYSTEM 521

2 TeachAnswer to Text Question

Why would it be harder tobreathe on top of moun-tains? Less dense air results inless total oxygen available forrespiration. As a result, the bodyfeels it must breathe in more air.

Quick DemoVisual-Spatial If possi-ble, obtain pig lungs

from a meat-packing house orbiological supply companyfor students to examine. Stu-dents are often surprised atthe light weight of the organs.Lead a discussion on whylungs aren’t heavy.

Answer to

Reading Check ✔

Breathing is the taking in and

expelling of air in our body.

Respiration is the process of

releasing energy from foods.

EnrichmentA person also experiences

oxygen deficiency in carbonmonoxide poisoning. Havestudents research how carbonmonoxide impairs delivery ofoxygen to tissues.

Physically Challenged An opera singer’sability to sing louder than an orchestra in alarge auditorium for an extended period oftime is called technique. Breath control is themainstay of technique. It enables singers notonly to sustain a long musical phrase but also

to increase or decrease the volume for dra-matic effect. Invite students who have studiedvoice or a wind instrument to perform for theclass and demonstrate breathing techniquesthey use. L2

Inclusion StrategiesInclusion Strategies

Page 520: 5a, 5bPage 521: 5a, 5b

CA Science ContentStandards

Oxygen suppliedto body

Breathing Circulation

Respiration

Oxygen carriedto body cells

Oxygen used inchemical reaction to

release energy from glucose

(inhale)

The RespiratorySystem

Functions of the Respiratory SystemPeople have always known that air and food are needed for

life. However, until about 225 years ago, no one knew why airwas so important. At that time, a British chemist discoveredthat a mouse couldn’t live in a container in which a candlehad previously been burned. He reasoned that a gas in the airof the container had been destroyed when the candle burned.He also discovered that if he put a plant into the container,whatever was necessary for life returned in eight or ninedays, and a mouse again could live in the container. What doyou think the plant produced when it was in the container?Think about photosynthesis. It had produced the gas neededfor life that was later named oxygen.

Breathing and RespirationPeople often get the terms breathing and respiration confused.

Breathing is the process whereby fresh air moves into and staleair moves out of lungs. Fresh air contains oxygen, whichpasses from the lungs into your circulatory system. Blood thencarries the oxygen to your individual cells. At the same time,your digestive system has prepared a supply of glucose in


19 1

The functions of the respiratory systemHow oxygen and carbondioxide are exchanged in thelungs and in tissuesThe pathway of air in and outof the lungsThree effects of smoking onthe respiratory system

Vocabularypharynx diaphragmlarynx chronic trachea bronchitisbronchi emphysemaalveoli asthma

Your respiratory system supplies oxygen and removescarbon dioxide from yourbody.

Why What You'll Learn

It's Important

You'll Learn

It's Important It's Important


It's Important

You'll Learn

It's Important

You'll Learn

Figure 19-1 Severalprocesses are involved in howthe body obtains, transports, andutilizes oxygen.


Prepare

PreplanningRefer to the Chapter Orga-nizer on pp. 518A–B.

1 Motivate

Tying to PreviousKnowledge

Recall the relationship ofthe circulatory system to thelungs. Remind students of therole of blood in providingoxygen to the body cells.

SECTION 19•1

Bellringer

Before presenting the lesson,display Section Focus Transparency 53 on the

overhead projector. Use the accompanying Focus Activityworksheet. ELLL2

Copyright©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

53

53

WATER WORLD

Scuba diving and snorkeling are activities that require special equipment

that allow you to breathe while your body is in the water. This equipment is

needed because unlike fish, which are adapted to breathe in oxygen dis-

solved in water, people breathe in oxygen from the air.

1. What special equipment is required for scuba diving? Why is this equip-

ment important?

2. How do divers and fish differ in the way they get oxygen?

SECTION FOCUS TRANSPARENCY

Section 19-1

Refer to Func-tions of the RespiratorySystem, Lungs, and HayFever and Pneumonia on pp. 518E–F.

ontent Background

ontent Background

CC

The following Teacher Classroom Resources can be used with Section 19-1:

Reproducible MastersActivity Worksheets, pp. 103–104, 107 Critical Thinking/Problem Solving, p. 19 Enrichment, p. 53 Laboratory Manual, pp. 111–116

Reinforcement, p. 53 Study Guide, pp. 73-74

TransparenciesTeaching Transparency 37 Science Integration Transparency 19 L2

L2

ELLL1

L2

L2

L2

L2

L2

Resource Manager

Pharynx, Larynx, and TracheaWarm, moist air now moves to the pharynx, a tubelike

passageway for both food and air. At the lower end of thepharynx is a flap of tissue called the epiglottis. When youswallow, the epiglottis folds down over the glottis, the open-ing between your vocal cords. By doing this, food or liquid isprevented from entering your larynx. The food goes intoyour esophagus instead. What do you think could happen ifyou talk or laugh while eating?

The larynx is the airway to which your vocal cords areattached. Look at Figure 19-4. When you speak, musclestighten or loosen your vocal cords. Sound is produced whenair moves past, causing them to vibrate.

Below the larynx is the trachea, a tube about 12 cm inlength. C-shaped rings of cartilage keep the trachea open andprevent it from collapsing. The trachea is lined with mucousmembranes and cilia to trap dust, bacteria, and pollen. Whyis it necessary for the trachea to stay open all the time?

Figure 19-4 Sound made by yourvocal cords gets louder with increasedair pressure. Pitch gets higher as muscles pull your vocal cords tighter,thus causing the glottis to close.

EpiglottisGlottisclosed

Vocalcords

Glottis open, showing theinner surface of the trachea

Trachea

Larynx

19-1 THE RESPIRATORY SYSTEM 523


Answers to Text Questions

What do you think couldhappen if you talk or laughwhile eating? Food might enterthe larynx and cause choking.Why is it necessary for thetrachea to stay open all thetime? If the trachea collapsed, itwould be difficult or impossibleto breathe.

Teacher FYIWhen a person chokes on a

piece of food, he or she oftencomments that “it went downthe wrong tube.” The phar-ynx serves as the passagewayof food into the esophagusand air into the trachea. Theepiglottis is a small flap of tis-sue that normally closes overthe tracheal opening whenfood is swallowed. Some-times food or liquid gets pastthe epiglottis and goes intothe trachea, triggering thechoking reflex.

ActivityKinesthetic Have stu-dents place their fingers

on the front of their necks, tilttheir heads backwards, andgently move their fingers upand down. Ask studentswhether they can feel theridges that are the rings ofcartilage around the trachea.

ELLL2

Using an AnalogyThe nasal cavity traps air

particles in a similar manneras a dust mask traps pollenfrom the air.

Music Divide the class into small groupsand distribute a balloon to each group. Askstudents to visualize the balloon as a lung andits neck as a trachea. Have students blow uptheir balloons, then stretch the opening into anarrow slit. Students should note the sound.Then have them stretch the slit to make it

longer and release a bit to make it shorter,noting the changes in pitch. Ask them to cor-relate the higher-pitched sounds and tauterstretch with the shorter vocal cords typical offemales and the lower-pitched sounds andlooser stretch with the longer vocal cords typ-ical of males. L3

Across the CurriculumAcross the Curriculum

Page 522: 5a, 5bPage 523: 5a, 5b



Organs of the Respiratory SystemYour respiratory system is made up of body parts that help

move oxygen into your body and carbon dioxide out of yourbody. The major structures and organs of your respiratorysystem are shown in Figure 19-3. These include your nasalcavity, pharynx (FER ingks), larynx (LER ingks), trachea(TRAY kee uh), bronchi (BRAHN ki), bronchioles (BRAHNkee ohlz), lungs, and alveoli. Air enters your body throughtwo openings in your nose called nostrils or through yourmouth. Once inside the nostrils, hair traps dust from the air.From your nostrils, air passes through your nasal cavity,where it gets moistened and warmed. Glands that producesticky mucus line the nasal cavity. The mucus traps dust,pollen, and other materials that were not trapped by the nasalhair. This helps filter and clean the air you breathe. Tiny hair-like structures, called cilia, move mucus and trapped mater-ial to the back of the throat where it can be swallowed.

Figure 19-3 Air can enter thebody through both the nostrils andthe mouth. What is the advantageof having air enter through the nostrils?

Compare the com-position of the air youinhale and the air youexhale by making twocircle graphs. Inhaledair is made up of78.62 percent nitro-gen, 0.5 percentwater vapor, 0.04 per-cent carbon dioxide,and 20.84 percentoxygen. Exhaled air ismade up of 74.5 per-cent nitrogen, 6.2percent water vapor,3.6 percent carbondioxide, and 15.7 per-cent oxygen.

Nasal passage

ThroatPharynxLarynx

Trachea

VeinsBronchi

Bronchioles

Alveoli

Epiglottis

Esophagus

Arteries


Caption AnswerFigure 19-3 It can be cleaned and warmed.

Use the Flex Your Brain activity to have students explore RESPIRATION.

Flex Your BrainFlex Your Brain

The circle graph of inhaled airis 283° nitrogen, 1.8° watervapor, 0.1° carbon dioxide,and 75° oxygen. The circlegraph of exhaled air is 268°nitrogen, 22° water vapor,13° carbon dioxide, and 57°oxygen.

VideodiscSTV: Human Body, Vol. 1Unit 1 Respiratory Tract 2:23

!8@_4>~A"12960-17279Refer to the Teacher Guide foradditional bar codes and teach-ing strategies.

CD-ROMGlencoe Science VoyagesInteractive CD-ROMExplorationsHave students do the interactiveexploration How do the parts ofthe respiratory system work to-gether?


How You BreatheBreathing is partly the result of changes in air pressure.

Under normal conditions, a gas moves from an area of highpressure to an area of low pressure. When you squeeze anempty plastic bottle, air rushes out. This happens becausepressure outside the top of the bottle is less than inside thebottle while your hand is gripping it. As you release yourgrip on the bottle, the pressure inside the bottle becomes lessthan outside the bottle. Air rushes back in, and the bottleresumes its shape.

Inhale and ExhaleYour lungs work in a similar way to the squeezed bottle.

Your diaphragm (DI uh fram) is a muscle beneath your lungsthat helps move air in and out of your body. It contracts andrelaxes when you breathe. Like your hands on the plastic bot-tle, the diaphragm exerts pressure or relieves pressure onyour lungs. Figure 19-6 illustrates breathing.

Figure 19-6 Your lungs inhaleand exhale about 500 mL of air with an average breath. This mayincrease to 2000 mL of air perbreath when you do strenuousphysical activity.

Trachea

Lungs

Diaphragm

Inhale Exhale

PHYSICS INTEGRATION

Breathing

ISUALIZINGV

ISUALIZING

G

V ISUALIZINGV

A When you inhale,your diaphragm contracts andmoves down. Theupward movementof your rib cage and the downwardmovement of yourdiaphragm causethe volume of yourchest cavity toincrease. Air pres-sure is reduced inyour chest cavity.Air under pressure outside the bodypushes into yourair passagewaysand lungs. Yourlungs expand asthe air rushes intothem.

B When you exhale,your diaphragmrelaxes and movesup to return to itsdome shape. Yourrib cage movesdownward. Thesetwo actions reducethe size of yourchest cavity. Yourlungs also return to their originalposition. Pressureon your lungs isincreased by thesetwo actions. Thegases inside yourlungs are pushedout through the airpassages.

Inhale Exhale


Using Science WordsAlvearium is the Latin word

for “beehive.” Think about theinternal structure of the bee-hive and relate this to the aircells of the lungs, the alveoli.

EnrichmentHave students research

how dry air taken in throughthe nostrils has about 100 per-cent humidity by the time itreaches the alveoli. L2

Figure 19-6 The positionof the diaphragm duringthe process of inhalingand expanding is shown.Compare this process withthe squeezing of the plas-tic bottle discussed in thetext.

LearningVISUAL

Discussion Interpersonal Discusswith students ways

singers practice their breath-ing in order to have greaterbreath control while singing.Physics The rate at which oxygen or car-

bon dioxide will diffuse across a respiratorysurface can be determined using Fick’s law.Have students find out what Fick’s law is.Fick’s law of diffusion states that the rate ofdiffusion of one substance in another is pro-portional to the negative gradient of theconcentration of the first substance. L2

Integrating the SciencesIntegrating the Sciences

The total amount of force exertedby a gas depends on the size ofits container. Pressure is theamount of force exerted per unitof area (P � F/A). Boyle’s lawstates that if you decrease the volume of a container of gas, thepressure of the gas will increase.If you increase the volume of thecontainer, the pressure will decrease.

Page 524: 5a, 5b, 7c, 7ePage 525: 5a, 5b


Vein

Bronchiole

(Right)Bronchus

Lung

Diaphragm

Capillaries

Alveolar sac

Artery

Alveoli

The Bronchi and the LungsAt the lower end of the trachea are two

short branches, called bronchi (singular,bronchus), that carry air into the lungs. Yourlungs take up most of the space in yourchest cavity. Within the lungs, the bronchibranch into smaller and smaller tubes. Thesmallest tubes are the bronchioles. At theend of each bronchiole are clusters of tiny,thin-walled sacs called alveoli (al VE uh li).As shown in Figure 19-5, lungs are actuallymasses of alveoli arranged in grapelikeclusters. Capillaries surround the alveoli.The exchange of oxygen and carbon diox-ide takes place between the alveoli andcapillaries. This happens easily because thewalls of the alveoli and the walls of thecapillaries are only one cell thick. Oxygendiffuses through the walls of the alveoliand then through the walls of the capillar-ies into the blood. There the oxygen ispicked up by hemoglobin in red blood cellsand carried to all body cells. Hemoglobin isa chemical that can carry oxygen and car-bon dioxide. As this takes place, carbondioxide is transported back from body cellsin the blood. It diffuses through the wallsof the capillaries and through the walls ofthe alveoli. Carbon dioxide then leavesyour body when you breathe out, or exhale.

Measuring Surface Area

Procedure

1. Make a cylinder out of a large sheet of paper.Tape it together.

2. Make cylinders out of small sheets of paper.Place as many as will fit inside the large cylinder without crushing the cylinders.

3. Unroll each cylinder. Place the small sheets nextto each other in a rectangle. Lay the large sheeton top.

Analysis

1. Compare the surface area of the large sheet withall the small sheets put together.

2. What do the large sheet and small sheets represent?

3. How does this make gas exchange more efficient?

Figure 19-5 About 300 million alveoli are ineach lung. The exchange of oxygen and carbondioxide with the environment takes place betweenthe alveoli and the surrounding capillaries. What isthe name for the energy-releasing process thatis fueled by oxygen?



For additional help doing this ac-tivity at home, see correspondingpages in the Home Involve-ment booklet.

Purpose

Visual-Spatial Studentsobserve and make infer-

ences about the increased surfacearea provided by alveoli.

Materialsone large piece of paper (81⁄2 � 14), 3 to 4 smaller piecesof paper (81⁄2 � 11, cut in half tomeasure 81⁄2 � 51⁄2), scissors,tape

Teaching StrategiesYou may want to use one color

for the large sheet of paper and adifferent color for the smallersheets.

Analysis1. Answers will vary depending

on student construction tech-niques, but will usually indicateat least a twofold increase insurface area.

2. The large piece of paper rep-resents a lung; the smallerpieces represent alveoli sacs.

3. More gas can be exchangedbecause there is greater sur-face area within the samespace.

Performance Have studentscalculate the surface area of a 10-cm � 20-cm cube and com-pare this with the surface area ofone hundred 1-cm � 1-cmcubes that have the same volumeas the larger cube. Use Perfor-mance Assessment in theScience Classroom, p. 29.

ELLL2

Assessment

Caption AnswerFigure 19-5 respiration

During one minute, while thebody is at rest, approximately 200 mL ofoxygen is used by body cells; an equalamount of carbon dioxide is produced.

ontent Background

ontent Background

CC


Diseases and DisordersIf you were asked to list some of the things that can harm

your respiratory system, you would probably put smoking atthe top. Many serious diseases are related to smoking. Beingaround others who smoke also can harm your respiratorysystem. Smoking, polluted air, and coal dust have beenrelated to respiratory problems such as bronchitis, emphy-sema, cancer, and asthma.

Chronic BronchitisBronchitis is a disease in which the bronchial tubes are

irritated and too much mucus is produced. Many cases ofbronchitis clear up within a few weeks, but sometimes thedisease will last for a long time. When bronchitis persists fora long time, it is called chronic bronchitis. Many cases ofchronic bronchitis result from smoking. People who havechronic bronchitis cough often to try to clear the mucus fromthe airway, as Figure 19-8 shows. However, the more a per-son coughs, the more the cilia and bronchial tubes can beharmed. When cilia are damaged, their ability to movemucus, bacteria, and dirt particles out of the lungs isimpaired. If this happens, harmful substances, such as stickytar from burning tobacco, build up in the airways. Sometimes,scar tissue forms, impairing theability of the respiratorysystem to function.

Figure 19-8 Cilia help trap andmove foreign matter that entersyour respiratory passageways.

A Coughing is a reflex thatmoves unwanted matterfrom respiratory passages.

Visit the GlencoeScience Web Site atwww.glencoe.com/sec/science/ca formore information aboutlung disease.

B Hairlike cilia in the respi-ratory passage areshown here. How dodamaged cilia weakenyour body’s defenseagainst disease?

Magnification: 3500 �


Caption AnswerFigure 19-8B Damaged ciliacannot trap and remove harmfulsubstances from the lungs.

For Internet tips, see Glencoe’s Using the Internet in the Science Classroom.

Internet Addresses

Visual-Spatial Immerse the fine-toothed end of an old comb into a

cup of water. Sprinkle pepper onto thewater-dipped end of the comb. Thisrepresents dust particles on the cilia ofthe air passages. Run a finger over thefine teeth to cause them to vibrate. Dothis five times and note that most of the

particles have been moved away. Wash thecomb. Pour several drops of molasses overthe fine-toothed end of the comb. Sprinklewith pepper. Repeat the running-of-the-finger process five times as describedabove. Note that the molasses (tar) hasprevented the cilia from removing thedust particles. ELLL2

Multiple Learning Styles

VideodiscThe Infinite Voyage: Crisisin the AtmosphereChapter 10 Los Angeles Smogand Air Quality Plan 6:30Refer to the Teacher Guide forbar codes and teaching strategies.

Teacher FYIHiccups are caused by spas-

modic contractions of the diaphragm. The result is asudden inhaling of air. Chok-ing could result if a reflex ac-tion did not automaticallycause the epiglottis to closeover the trachea and preventany food from entering.

Page 526: 5bPage 527: 5a, 5b, 7b



A Life-Saving ManeuverThe epiglottis closes over your larynx to stop food from

entering the trachea. Sometimes, this process does not hap-pen quickly enough. Each year, thousands of people diebecause food or other objects become lodged in the trachea.Air flow between the lungs and the mouth and nasal cavity isblocked. Death can occur in a matter of minutes.

Pressure Dislodges the FoodRescuers use abdominal thrusts (also called the Heimlich

maneuver), Figure 19-7, to save the life of a choking victim.CAUTION: This maneuver can cause harm and should be doneonly if necessary. The theory behind this maneuver is to usepressure to force out the food or object. When the diaphragmis forced up, the volume of the chest cavity quickly decreases.Pressure is suddenly increased. Air is forced up in the tra-chea. There may be enough force to dislodge food or anobject. The victim is able to breathe again.

Food in trachea

Rescuer’s fist

Bottom ofrib cage

Hand-over-fistposition

Navel

Pressure

Figure 19-7 Abdominalthrusts are used to save a personfrom choking.

A The rescuer stands behind the choking victim. He or sheplaces a fist (thumb-side in)against the victim’s stomach.The fist should be below theribs and above the navel.

B With a sudden, sharp move-ment, the fist is thrust up andinto the area below the ribs.


ActivityLinguistic Have stu-dents check the daily

newspapers for air qualityconditions and air pollutionalerts. Relate this to peoplewith respiratory disorders. L2

Figure 19-7 Review thetheory behind why abdom-inal thrusts work. This ma-neuver used to be calledthe Heimlich maneuver.Abdominal thrusts lift thediaphragm and forceenough air from the lungsto create an artificial cough.The cough is intended tomove and expel an ob-structing foreign body inan airway. Each thrustshould be given with theintent of removing the ob-struction.

LearningVISUAL

Health Arrange a visit to a Red Cross cen-ter or have a health specialist come to schooland demonstrate how to use abdominalthrusts and the cardiopulmonary resuscita-tion (CPR) method to revive a person who isnot breathing.


Teacher FYIA field guide to First Aid oc-

curs at the end of the chapteron Immunity. This guidecould be referenced as abdom-inal thrusts are discussed.



AsthmaSome lung disorders are common

in nonsmokers. Asthma (AZ muh) isa disorder of the lungs in whichthere may be shortness of breath,wheezing, or coughing. When a per-son has an asthma attack, thebronchial tubes contract quickly.Asthma attacks are generally treatedby inhaling drugs that enlarge thebronchial tubes. Asthma is often anallergic reaction. An asthma attackcan result from a reaction to breath-ing certain substances, such as ciga-rette smoke or plant pollen. Eating certain foods or stress alsohave been related to the onset of asthma attacks.

Except for certain bacteria, all living things would die with-out oxygen. Your respiratory system takes in oxygen and getsrid of carbon dioxide. This system also helps get rid of somepathogens. You can help keep your respiratory system healthyby avoiding smoking and breathing polluted air. Regularexercise helps increase your body’s ability to use oxygen.

Figure 19-10 More than 85percent of all lung cancer is relatedto smoking.

Use libraryreferences to find out

about a lung diseasecommon among coalminers, stonecutters,and sandblasters. Inyour Science Journal,write a paragraphabout the symptoms ofthis disease. Researchwhat safety measuresare now required whenworking with coal and rock.

1. What is the main function of the respiratory system?2. How are oxygen and carbon dioxide gases exchanged in

the lungs and in body tissues?3. What causes air to move in and out of the lungs?4. How does emphysema affect a person’s alveoli?5. Think Critically: How is the work of the digestive and

circulatory systems related to the respiratory system?

6. Skill BuilderMaking Models Lungs are important organs

used in the process of respiration. Do the Chapter 19Skill Activity on page 724 and make a model of howlungs function.

Section AssessmentSection Assessment


1. supplies oxygen to theblood and removes carbondioxide

2. Oxygen and carbon diox-ide are exchanged viablood.

3. movement of the di-aphragm and rib cage anddifferences in pressure

4. Alveoli stretch and losetheir elasticity.

5. Think Critically The di-gestive system providesfood for respiration incells. The circulatory sys-tem transports oxygen tobreak down food and car-ries respiration wasteproducts to the lungs tobe expelled.


AssessmentPortfolio Review student responses to theFlex Your Brain activity. In step 2, studentsmight list how breathing feels, its function,what affects breathing, or things that inter-fere with breathing. Use Performance As-sessment in the Science Classroom, p. 105.P

Black lung is caused by in-halation of mineral dustssuch as silica and coal dust.Fibrous tissue developsaround the particles, re-placing lung tissue. Lessgas exchange takes place.Safety measures now usedinclude protective clothingand masks, ventilation, wetdrilling and water sprayingto reduce dust, and atmos-pheric monitoring systems.

Page 528: 5a, 5bPage 529: 5a, 5b, 7d


Figure 19-9 Lung diseases canhave major effects on breathing.

A A normal, healthy lungcan exchange oxy-gen and carbondioxide effectively.


EmphysemaA disease in which the alveoli in the lungs lose their ability

to expand and contract is called emphysema (em fuh SEEmuh). Most cases of emphysema result from smoking. In fact,many smokers who are afflicted with chronic bronchitiseventually progress to emphysema. When a person hasemphysema, cells in the bronchi become inflamed. Anenzyme released by the cells causes the alveoli to stretch andlose their elasticity. As a result, alveoli can’t push air out ofthe lungs. Less oxygen moves into the bloodstream from thealveoli. Blood becomes low in oxygen and high in carbondioxide. This condition results in shortness of breath. Asshown in Figure 19-9, some people with emphysema can’tblow out a match or walk up a flight of stairs. Because theheart works harder to supply oxygen to body cells, peoplewho have emphysema often develop heart problems, as well.

Lung CancerLung cancer is the third leading cause of death in men and

women in the United States. Inhaling the tar in cigarette smokeis the greatest contributing factor to lung cancer. Once in thebody, tar and other ingredients found in smoke are changedinto carcinogens (kar SIHN uh junz). These carcinogens triggerlung cancer by causing uncontrolled growth of cells in lung tis-sue. Smoking also is believed to be a factor in the developmentof cancer of the mouth, esophagus, larynx, and pancreas.Figure 19-10 shows one way people are encouraged not tosmoke.

B A diseased lung cuts downon the amount of oxygenthat can be delivered tobody cells.

C Emphysema may take 20 to30 years to develop.

At the beginning of this chapter, youdetermined yourbreathing rate for oneminute. Use that num-ber to calculate howmany breaths you takein a day. If every twobreaths filled a literbottle, how many bottles would you fillin a day?


3 AssessCheck for UnderstandingActivity

Linguistic Have stu-dents write a paragraph

describing why air moves intothe lungs when the ribs moveupward and the diaphragmmoves downward.

ReteachUse a lung demonstration

apparatus to illustrate howthe downward movement ofthe diaphragm causes re-duced air pressure within thechest cavity.

ExtensionFor students who have

mastered this section, use theReinforcement and Enrich-ment masters.

4 CloseProficiency PrepUse this quiz to check stu-dents’ recall of section content.

1. What keeps the tracheatube from collapsing?rings of cartilage

2. Masses of what stuctureare described as grape-like clusters? alveoli

L2

L2

Answers will vary dependingon individuals’ breathingrates. Example: An adult in-hales about 12 times eachminute at rest. In one day, aperson exhales and inhales 12 breaths/minute � 60 min-utes/hour � 24 hours/day, orabout 17 280 times. If a per-son exercises, this number in-creases; 8640 bottles. P

Factors that trigger asthma irritateairways but they do not cause inflammationand therefore do not cause asthma. Airwayswill react more quickly to triggers if inflam-mation is already present in the airways.Common triggers include everyday stimulisuch as cold air, dust, strong fumes, exercise,

inhaled irritants, emotional upsets, andsmoke. The most common causes of asthmainclude respiratory viral infections and aller-gens. The most common inhaled allergensinclude pollen, animal secretions (especiallycats and horses), molds, and dust mites.

ontent Background

ontent Background

CC

Test Your Hypothesis

Analyze Your Data

Draw Conclusions

Plan1. As a group, agree upon and

write out the hypothesis statement.

2. As a group, list the steps thatyou will need to take to test yourhypothesis. Consider each of thefollowing factors. How will youintroduce the exhaled air into thebromothymol blue solution?How will you collect data onexhaled air before and afterphysical activity? What kind ofactivity is involved? How long will it go?

3. List your materials. Yourteacher will provide instructionon safe procedures for usingbromothymol blue.

4. Design a data table and recordit in your Science Journal so thatit is ready to use as your groupcollects data.

5. Read over your entire experi-ment to make sure that all thesteps are in logical order.

6. Identify any constants, vari-ables, and controls of the experiment.

Do1. Make sure your teacher

approves your plan before you proceed.

2. Carry out the experiment as planned.

3. While the experiment is goingon, write down any observationsthat you make and complete the data table in your ScienceJournal.

1. What caused the bromothymolblue solution to change color?What color was it at the conclu-sion of each test?

2. What was the control? What wasthe constant(s)? What was thevariable(s)?

3. Compare the time it tookthe bromothymol bluesolution to change colorbefore exercise and afterexercise. Explain any difference.

4. Prepare a table of your data andgraph the results.

1. Did exercise affect your rate of respiration? Explain youranswer using data from yourexperiment.

2. Using your graph, estimate thetime of color change if the timeof your physical activity weretwice as long.

Using Scientific MethodsUsing Scientific Methods

19-1 THE RESPIRATORY SYSTEM 53119-1 THE RESPIRATORY SYSTEM 531


Teaching StrategiesTell interested students that the

carbon dioxide that bubbled intothe water forms carbonic acid,which causes the color change inthe bromothymol blue solution.

Expected OutcomeResults will reveal that more car-

bon dioxide is exhaled after exer-cising, and the bromothymol bluesolution changes color from blueto yellow more quickly.

Error AnalysisHave students compare their re-

sults with those of others and deter-mine whether the procedures werefollowed correctly.

1. the presence of carbon diox-ide; yellow

2. control—breathing into beakerA, which contained the solutionbefore exercising; constant—amount of bromothymol blue;variable—amount of exercise

3. The solution takes less time tochange color after exercise.Exercise produces more car-bon dioxide.

4. The table should contain all thedata collected. The graph shouldaccurately reflect the data.

1. Answers will vary, but theyshould show a change in therate. Students active in physicalactivities may show less of arate change. Students shoulduse data from activity to defendtheir answers.

2. Estimates will vary, but should in-dicate that it would take less timefor a color change if the physicalactivity were twice as long.

Analyze Your Data

Draw Conclusions

Performance To further assess students’ abilities to analyze the effects of respiration, havethem design an experiment to detect the watervapor exhaled in an hour or in a day. Use Per-formance Assessment in the ScienceClassroom, p. 23.

Assessment

Have students brainstorm methods for testingfor moisture in exhaled air. Breathe on a cool,shiny metal or glass surface; minute waterdroplets can be seen and felt. Paper treated withcobalt chloride will turn from blue to pink whenit comes in contact with moisture.

Page 530: 5a, 5b, 7a, 7c,7ePage 531: 5a, 5b, 7a, 7c,7e


Activity

19•1Design Your OwnExperiment

Possible Materials• Clock or watch with

second hand• Drinking straws• Bromothymol blue

solution (200 mL)• Glass cups (12 oz) (2)

*beakers (400 mL) (2)• Metric measuring cup

*graduated cylinder(100 mL)

*Alternate Materials

Goals• Observe the effects of the

amount of carbon dioxide on the bromothymol bluesolution.

• Design an experiment thattests the effects of a variable,such as the amount of carbondioxide exhaled before andafter exercise, on the rate atwhich the solution changescolor.

Safety Precautions

Protect clothing from the solu-tion. Wash hands after using thesolution. CAUTION: Do notinhale the solution through thestraw.

The Effects ofExercise onRespiration

Breathing rate increases with an increase in physical activity. Abromothymol blue solution changes color when carbon dioxide

is bubbled into it. Can you predict whether there will be a differencein the time it takes for the solution to change color before and afterexercise?

How will an increase in physical activity affect the amount of car-bon dioxide exhaled?

State a hypothesis about how exercise will affect the amount ofcarbon dioxide exhaled by the lungs.

Activity 19 1Activity 19 1

Recognize the Problem

Form a Hypothesis



Purpose

Logical-MathematicalStudents will design and

carry out an experiment to showhow exercise affects the amount ofcarbon dioxide exhaled by thelungs.

Process Skillshypothesizing, designing an experi-ment, observing and inferring, in-terpreting data, making and usingtables, recognizing cause and effect

Time45 to 50 minutes

Alternate MaterialsLimewater (a saturated Ca(OH)2solution) can be used instead ofbromothymol blue. CO2 causes acloudy white precipitate to formwhen added to limewater.

Safety PrecautionsDo not let students share the

same straw. Before the studentsexercise, make sure no student hasa medical problem that exercisewould complicate. Bromothymolblue is a skin irritant. Wash handsafter use.

Possible Hypothesis It will take less time to cause a

change in the bromothymol bluesolution after exercising than be-fore exercising.

Possible ProcedureLabel the beakers A and B. Use

beaker A for the resting test andbeaker B for the activity test. Pour100 mL of bromothymol blue so-lution into each beaker. Exhalethrough the straw into the solution.Continue exhaling for 15 secondsor until the bromothymol blue so-lution changes color. Record thetime it takes for the color changeto occur. Exhale using the sameforce for both tests.

PCOOP LEARNELLL2

Recognize the Problem

Form a Hypothesis

Test Your Hypothesis

Sample Data Table

Student Time—before Time—after exercising (s) exercising (s)

A 15 13

B 12 10

C 13 12

D 15 14

Gifted Have students investigate why thebromothymol blue solution changes color.They can try other acid-base indicators suchas blue litmus solution.

Inclusion StrategiesInclusion Strategies

The ExcretorySystemFunctions of the Excretory System

Just as wastes, in the form of sewage or garbage, areremoved from your home, your body also eliminates wastesby means of your excretory system. Undigested material iseliminated by your digestive system. The waste gas, carbondioxide, is eliminated through the combined efforts of yourcirculatory and respiratory systems. Some salts are elimi-nated when you sweat. Together, these systems function as apart of your excretory system. If wastes aren’t eliminated,you can become sick. Toxic substances build up and damageorgans. If not corrected, serious illness or death occurs.

Figure 19-11 shows how the urinary system functions as apart of the excretory system. The organs of your urinary sys-tem are excretory organs. Your urinary system is made up oforgans that rid your blood of wastes produced by the metab-olism of nutrients. This system also controls blood volume byremoving excess water produced by body cells. A specificamount of water in blood is important to maintain normalblood pressure, the movement of gases, and excretion of solidwastes. Your urinary system also balances specific concentra-tions of certain salts and water that must be present for cellactivities to take place.

19 2 THE EXCRETORY SYSTEM 533

19 2

How to distinguish betweenthe excretory and urinary systemsHow to describe how yourkidneys workWhat happens when urinaryorgans don’t work

Vocabularyurinary urine

system ureterkidney bladdernephron urethra

The urinary system helpsclean your blood.


It's Important

You'll Learn

It's Important It's Important


It's Important

You'll Learn

It's Important

You'll Learn

Figure 19-11 The urinary system is linked withthe digestive, circulatory, and respiratory systems,as well as skin to make up the excretory system.

Water and undigestedfood out

Carbon dioxideand water out

Excretion

Salts and someorganic substances

Excess water, metabolicwastes, and salts out

Food and liquid in Oxygen in Sweat Water and salts in

DigestiveSystem

RespiratorySystem Skin

UrinarySystemC

19-2 THE EXCRETORY SYSTEM 533

Prepare

PreplanningRefer to the Chapter Orga-nizer on pp. 518A–B.

1 Motivate

SECTION 19•2

Bellringer

Before presenting the lesson,display Section Focus Transparency 54 on the

overhead projector. Use the accompanying Focus Activityworksheet. ELLL2

Copyright©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

54

54

REMOVING LIQUID WASTESDo you perspire heavily when you exercise? Perspiration is a liquid waste

given off by the body. It contains mostly water and dissolved salts.

1. In addition to eliminating waste materials, in what other way is perspir-

ing helpful to the body?2. Why is it important to drink plenty of fluids when you are involved in

activities that cause you to perspire heavily?3. What other body system is involved in the removal of liquid wastes?


Refer to YourUrinary System, Urine, andUrinary Tract Infections onp. 518F.

ontent Background

ontent Background

CC

The following Teacher Classroom Resources can be used with Section 19-2:

Reproducible Masters

Activity Worksheets, pp. 105–106, 108

Enrichment, p. 54

Multicultural Connections, pp. 37–38

Reinforcement, p. 54

Transparencies

Teaching Transparency 38 L2

L2

L2

L3

L2

Resource Manager

Page 533: 5a, 5b



How it WorksScubaFor humans, having a constant supply of oxygen is a matter oflife or death. People get the oxygen they need from the airthey breathe. This means swimmers can stay underwater onlyfor as long as they can hold their breath. Those who want todive deeper and stay underwater longer must use scubaequipment. Scuba stands for Self-Contained UnderwaterBreathing Apparatus.

Geared for the DepthsThree pieces of equipment (on the diver, right) enable divers to spend a longer period of time underwater: (1) a buoyancy-control device, or BCD, (2) a scuba tank, and (3) a regulator.

BCD Before the dive, the BCD—an inflatable vest or jacket—is partially filled with air. The diver descends by letting air outof the BCD. The diver maintains his or her position at differentdepths by controlling the amount of air in the BCD.

Scuba tank Worn on the diver’s back, the tank holds a largeamount of compressed air—air that has been squeezed into asmaller space under high pressure. The diver breathes the airin this tank while underwater. The compressed air in the scuba tank also is used to add air to the BCD to increase a diver’s buoyancy (make a diver rise in the water).

Regulator On the water’s surface, air pressure in the lungs isequal to outside air pressure, measured as atmospheres (atm).Pressure increases at a rate of 1 atm for each 10 m underwater.As a diver descends, the regulator automatically compensatesfor the increase in depth (and thus, pressure). So, the regulatorsupplies air from the tank to the diver at the same pressure asthe surrounding water. The diver never feels squeezed by theincreased pressure of the deeper water.

Think Critically1. The volume of air increases as pressure decreases. Relate

this to the fact that divers should never hold their breathas they ascend.

2. Why does a diver use a weight belt in addition to a BCDwhen diving?

Professional scuba divers are paidto dive for specific purposes.Professional divers work for themilitary, the government, andcommercial agencies. A militarydiver may look for a hiddenbomb under the sea. A com-mercial diver may work on anoil platform. Law enforcementagencies often hire divers tolook for missing bodies orweapons.

How it Works

CareerCONNECTION

GEARED FOR THE DEPTHS

1

2

3

2

3

1



Thinking Critically1. The air in their lungs would increase,

causing great pain.2. Most people have a natural positive

buoyancy. The BCD adds more buoyancy. Therefore, a weight belt isneeded to achieve negative buoyancyfor the diver to sink below the watersurface.

ontent Background

ontent Background

CC

CareerCONNECTION

Scuba diving schools offer various levelsof training, from recreational divers to com-mercial divers. Contact your local divingschool for local requirements or contact TheNational Association of Scuba DivingSchools for more information.

PurposeStudents are introduced toscuba gear and how it helpsscuba divers swim and breatheunderwater.

Most recreational diving isdone between 10 m and 27 m.Professional and technicaldivers often dive muchdeeper. A person cannotbreath compressed air con-tained in a scuba tank with-out a two-stage regulator be-cause the pressure is toogreat. When a diver dives to30 m, the regulator must pro-vide 4 atm of pressure toallow the same breath (1 atmto compensate for the weightof air and 3 atm to compen-sate for the weight of thewater above).

Ask students to lookclosely at the photographof the scuba diver andequipment. Ask studentswhy they think the divermight be carrying an extraregulator. In case the diverruns out of air, the divers canshare air from another per-son’s tank.

LearningVISUAL

Teaching StrategiesHave students research andreport on the cause and treat-ment of decompression illness(the bends). Study Guide, pp. 75-76 ELLL1


Urine Collection and ReleaseThe urine in each collecting tubule

drains into a funnel-shaped area of eachkidney that leads to the ureters (YER uturz). Ureters are tubes that lead from eachkidney to the bladder. The bladder is anelastic, muscular organ that holds urineuntil it leaves the body. Figure 19-13 showshow the shape of the cells that make up thelining of the bladder changes with theamount of urine stored in it. A tube calledthe urethra (yoo REE thruh) carries urinefrom the bladder to the outside of the body.

Other Water Loss Other parts of the excretory system also

help your body maintain proper fluid levels. In addition to losing salt, an adultloses about 0.5 L of water each day throughperspiration. When air is exhaled, you alsolose water. When you see your breath on acold day or breathe on a cold windowpaneand notice water vapor, you see this mois-ture. Each day, about 350 mL of water areremoved from your body through your res-piratory system. A small amount of wateralso is expelled with the undigested mate-rial that passes out of your digestive system.

Figure 19-13 The elas-tic walls of the bladder canstretch to hold up to 500 mLof urine. When empty, thebladder looks wrinkled (A).The cells of the lining arethick. When full, the bladderlooks similar to an inflated bal-loon (B). The cells of the liningare stretched and thin.

Modeling Kidney Function

Procedure

1. Mix a small amount of soil with water in a cupto make muddy water.

2. Place a funnel into a second clean cup.3. Place a piece of filter paper into the funnel.4. Carefully pour the muddy water into the funnel.

Analysis

Compare this filtering process to the function ofkidneys inside your body.

Bladder lining

Muscle

Cells of lining

Urethra

Ureter

A Empty urinarybladder

B Full urinarybladder


Purpose

Kinesthetic Studentswill model and observe the

function of a kidney.

Materialsdirt (2 T), 8-ounce plastic cup (2),funnel, filter paper, tap water

Teaching StrategiesTroubleshooting Moisten fil-ter paper before filtering the dirtywater so that the paper adheresto the funnel.

AnalysisThe filter removes the dirt and

particles. Only the liquid goesthrough. The filter is like anephron, through which all liquidpasses. The nephrons keepwaste from passing through.

Portfolio Have students makea labeled drawing of the urinarysystem. Have them place arrowson the diagrams to show the flowof fluids through the nephron tothe bladder and then out of thebody. Use Performance As-sessment in the ScienceClassroom, p. 55.

P

Assessment

Mathematics Calculate the ratio of bodyweight to amount of urine excreted. If an11-kg child excretes 600 mL, what wouldyou expect a 45-kg person to excrete? 2455mL However, the amount is actually onlyabout 1500 mL. The amount excreted bychildren is greater in proportion to theirweight.


Using an AnalogyIn the filtering model con-

structed in the above activity,have students infer what eachpart (muddy water, filter,clear water) represents withinthe human body. L2

Page 534: 5a, 5b, 7bPage 535: 5a, 5b, 7c, 7e



Organs of the Urinary SystemThe major organs of your urinary system, as shown in

Figure 19-12, are two bean-shaped kidneys. Kidneys arelocated on the back wall of the abdomen at about waist level.The kidneys filter blood that has collected wastes from cells.All of your blood passes through your kidneys many times aday. In Figure 19-12, you can see that blood enters the kid-neys through a large artery and leaves through a large vein.

The Filtering UnitEach kidney is made up of about 1 million nephrons (NEF

rahnz), the tiny filtering units of the kidney. Each nephronhas a cuplike structure and a duct. Blood moves from therenal artery to capillaries in the cuplike structure. Water,sugar, salt, and wastes from your blood pass into the cuplikestructure. From there, the liquid is squeezed into a narrowtubule. Capillaries that surround the tubule reabsorb most ofthe water, sugar, and salt and return it to the blood. Thesecapillaries merge to form small veins. The small veins mergeto form the renal veins, which return purified blood to yourmain circulatory system. The liquid left behind flows into collecting tubules in each kidney. This waste liquid, or urine,contains excess water, salts, and other wastes not reabsorbedby the body. The average adult produces about 1 L of urineper day.

Figure 19-12 The urinary system (A) is made of your kid-neys, bladder, and the connectingtubes. The kidneys (B) are made up of many nephrons (C). A singlenephron is shown in detail. What isthe main function of the nephron?

Aorta TubuleCapillary

Collectingduct

Urine toureter

Nephron

ArteryVein

Renalartery

Renalvein

UrethraUrinarybladder

Ureter

Kidney

KidneyUrinary System

A B C

Visit the GlencoeScience Web Site atwww.glencoe.com/sec/science/ca formore information abouthow kidneys work.


2 Teach

Figure 19-12 Have stu-dents trace the pathway ofthe blood to, through, andfrom the kidney.

LearningVISUAL

Caption AnswerFigure 19-12 filtering theblood

The amount of urine that is secreted by the body is affected by theamount of water or salt that is ingested.Drinking large amounts of water increasesurine output. Eating lots of salty foodsdecreases urine output.

ontent Background

ontent Background

CC

Tying to PreviousKnowledge

Recall the function of a filterin a coffee-making machine.Only liquid is allowed to flowthrough. Have students com-pare this with the function ofthe urinary system.

EnrichmentVisual-Spatial Havestudents construct a cir-

cle or a bar graph to illustratethe composition of urine.Water � 95 percent, urea �2 percent, sodium chloride �1 percent, other substances �2 percent.

Quick DemoSet up a diffusion experi-

ment using a cellophane bagwith a colored sugar solutionplaced in a container ofwater.

L3

For Internet tips, see Glencoe’s Using the Internet in the Science Classroom.

Internet Addresses


If too little water is in the blood, more of the hormone isreleased by your hypothalamus and more water is returnedto the blood. The amount of urine excreted decreases. At thesame time, your brain sends a signal that causes you to feelthirsty. You drink liquids to quench this thirst. Figure 19-15illustrates the different sources of fluid intake and outputwithin your body.

Diseases and Disorders What happens when someone’s urinary organs don’t work

properly? Waste products that are not removed build up andact as poisons in body cells. Water that normally is removedfrom body tissues accumulates and causes swelling of theankles and feet. Sometimes, fluids also can build up aroundthe heart. The heart must work harder to move less blood tothe lungs. Without excretion, an imbalance of salts may occur.The body responds by trying to restore this balance. If the balance is not restored, the kidneys and other organs can be damaged.

Water in foods

Fluids

Stomach

Intestines

Bloodvessel

Body uses nutrients Kidney

H2O

H2O

H2O

H2O

Largeintestine

Skin

Lungs

Sweatgland

Some wateris returned

Figure 19-15 Fluids aretaken in by the body through differ-ent sources and expelled in differ-ent ways. The brain must balancethe fluid levels in your body.

INTEGRATIONPHYSICS

Kidney StonesSmall, solid particles mayform in the kidneys. If thesestones pass into the ureter,severe pain results. Onemethod of kidney stoneremoval involves the use of alithotripter. This machine pro-duces sound waves thatcause the stones to breakinto small pieces. Thesepieces are carried out of thebody in urine.



Guided Reading Strategy

EnrichmentInterpersonal Have stu-dents research the ad-

vances made in dialysis machines and procedures. Dis-cuss what changes mightoccur to a person’s lifestylewhen he or she needs to un-dergo dialysis. What activityrestrictions result from theneed for dialysis treatment?

3 AssessCheck for UnderstandingQuick Demo

Visual-Spatial Use ananatomical model or

chart and have students tracethe flow of blood through theurinary system and explainthe functions of each organ.

ReteachVisual-Spatial Havestudents prepare a basic

diagram of the sequence oforgans involved in the pro-cessing of liquid wastes in thebody.

ExtensionFor students who have

mastered this section, use theReinforcement and Enrich-ment masters.

L1

ELLL2

L3

Four-Corner Discussion This strategy en-

courages the class to debate a complex issue.

Make four signs: Strongly Agree, Agree, Dis-

agree, Strongly Disagree. Place one sign in

each corner of the room. Write on the chalk-

board a statement that will elicit reactions

from students. Have the students respond on

paper to the statement. After several minutes,

direct them to move to the corner with the

sign that most closely reflects their opinions.

In the corners, students share responses.

Each group then selects a spokesperson to re-

port the opinions of the group. After all

groups have reported, open the floor for de-

bate. Allow students who have changed their

opinions to change corners. Have students

conduct a Four-Corner Discussion about the

causes of respiratory diseases.

In addition to chemicals, lasershave been used to break up kidneystones. Invite a health specialist todiscuss how new technologies arebeing used to break up stones inthe gall bladder and kidneys.

Page 536: 5a, 5bPage 537: 5a, 5b


Balancing Fluid LevelsTo maintain good health, the fluid levels within your body

must be balanced and your blood pressure must be main-tained. This happens because an area of your brain, the hypo-thalamus, is involved in controlling your body’s homeostasis(hoh mee oh STAY sus). The hypothalamus produces a hor-

mone that regulates how much urineis produced. Figure 19-14 shows

what happens when there is toomuch water in your blood.

Figure 19-14 The amount ofurine that you eliminate each day isdetermined by the level of a hor-mone. This hormone is producedby your hypothalamus.

Increased level ofliquid in blood

Hypothalamus

A Your brain detects too much water inyour blood. Your hypothalamus thenreleases a lesser amount of hormone.

B This release signals thekidneys to return lesswater to the blood andincrease the amount ofurine excreted.

Analyzing Water Gain and Loss

Cell activity and body functions depend on water. Thebalance of water must be maintained. Table A showsthe major sources by which body water is gained.

Table B lists the major sources by which body wateris lost.

Construct tables and calculate the percentages ofsources of gain and loss of water. Complete yourtable with these data.

Think Critically

1. What is the greatest source of liquids gained byyour body?

2. How would the percentages of water gained andlost change in a person who was working inextremely warm temperatures? What organ of the body would be the greatest contributor towater loss?


Source Amount (mL) Percent

Oxidationof nutrients 250 10

Foods 750 30

Liquids 1500 60

Total 2500

Major Sources by WhichBody Water Is Gained

Source Amount (mL) Percent

Urine 1500 60

Skin 500 20

Lungs 350 14

Feces 150 6

Total 2500

Major Sources by WhichBody Water Is Lost

Table ATable B


Correcting Misconceptions

Students often do not rec-ognize the need for drinkingadequate amounts of watereach day. Water is necessaryfor the proper functioning ofthe kidneys. Water leaves ourbodies through perspirationfrom the skin, through watervapor in exhaled breath, andin urine.

EnrichmentLogical-MathematicalAdult kidneys weigh

only about 170 g each. Thekidneys of an average adultprocess about 1600 L of liquidper day, most of which is re-cycled. Have students calcu-late how many liters anadult’s kidneys process in ayear, in a decade, and in 75years. 584 000 L; 5 840 000 L;43 800 000 L L2

Kidneys function to conservewater. If they did not conserveour body fluids, we wouldhave to drink many gallons ofwater each day in order tosurvive. See annos on studentpage for percentages.

Think Critically1. ingested liquids 2. Less water would be

taken in and more waterwould be lost; the skin.

Making an Analogy Ask students towrite an essay in which they compare akidney to a recycling center. Have themconsider substances that can be reusedand those that cannot be recycled.

Activity

19•2Kidney StructureAs your body uses nutrients, wastes are created. One role of

kidneys is to filter waste products out of the bloodstreamand excrete this waste outside the body.

What You’ll InvestigateHow does the structure of the kidney relate to its

function?

Goals• Observe the external and internal structures of

a kidney.

Procedure 1. Examine the kidney supplied by your teacher.2. If the kidney is still encased in fat, peel the fat

off carefully.3. Using a scalpel, carefully cut the tissue length-

wise in half around the outline of the kidney.This cut should result in a section similar to theillustration on this page.

4. Observe the internal features of the kidneyusing a hand lens, or view the features in amodel.

5. Compare the specimen or model with the kid-neys in the illustration.

6. Draw the kidney in your Science Journal andlabel the structures.

Conclude and Apply1. What part makes up the cortex of the kidney?

Why is this part red?2. What is the main function of nephrons?3. The medulla of the kidney is made up of a net-

work of tubules that come together to form theureter. What is the function of this network oftubules?

4. How can the kidney be compared to a portablewater-purifying system?


Using Scientific MethodsUsing Scientific Methods

Materials• Large animal kidney• Scalpel• Hand lens

Activity 19 2


PurposeVisual-Spatial Studentswill examine the structures

visible in a large animal’s kidneyand relate each structure to itsfunction.

Process Skillsobserving and inferring; interpret-ing scientific illustrations; compar-ing and contrasting

Time45 to 50 minutes

MaterialsLarge animal’s kidney (for exam-ple, pig), scalpel, magnifying glass

Safety PrecautionsCaution students about the use

of sharp objects.

Teaching StrategiesYou may wish to have some kid-

neys remain whole. Other kidneysmay be already sliced longitudi-nally. These kidneys can be usedover and over.Troubleshooting Demonstratethe proper techniques for using thescalpels.

Answers to Questions1. The mass of nephron units; the

color is due to the blood in thenephrons.

2. filters blood within the kidney3. The network of tubules moves

the fluid from the nephrons. Asthe fluid is moved along, somewater, sugar, and salt are reab-sorbed into the bloodstream.Eventually, the fluid collects inthe bladder.

4. Both serve as filtering mecha-nisms.

Oral Have students describe the evidence thattwo kidneys are more than enough to take careof excretory functions. Use Performance As-sessment in the Science Classroom, p. 71.

Assessment

Page 538: 5a, 5bPage 539: 5a, 5b, 7c, 7e



4 CloseProficiency PrepUse this quiz to check stu-dents’ recall of section content.

1. What are your main ex-cretory organs? kidneys,lungs, skin

2. What is the filtering unitof the kidneys? thenephron

1. rids the body of wastes,controls blood volume byremoving excess water,balances salts and water

2. Kidneys filter the blood toremove wastes, water, andsalt. Necessary amountsof water, sugar, and saltare returned to the blood.

3. The excretory system in-cludes all the organs thatfunction to rid the bodyof a variety of wastes. Theurinary system has or-gans that function to pro-duce only one kind ofwaste, urine.

4. Think Critically Many ofthe substances are neededby the body.


AssessmentPortfolio Provide students with a diagramof the circulatory, respiratory, and excretorysystems. Have them trace the steps fromtheir concept maps. Use Performance As-sessment in the Science Classroom, p. 105.P

5. Skill BuilderThe concept map shouldshow that wastes in blood are

carried to the lungs, which removewater and carbon dioxide, and to thekidneys, which remove water and ex-cess salts.

Answer to

Reading Check ✔

a process by which blood

from a person's artery is

pumped through tubing

bathed in a salt solution so

that wastes are removed


Figure 19-16 Peritonealhemodialysis is a procedure thatcan be done at home for many dialysis patients. Dialysis fluid ispumped into the stomach cavity.Waste products then move fromthe blood vessels into the fluid,which is then drained from thepatient.

All 5 L of blood inthe body pass throughthe kidneys in approx-imately five minutes.Calculate the averagerate of flow throughthe kidneys in litersper minute.

✔Reading Check

What is dialysis?

DialysisPersons who have damaged kidneys may need to have

their blood filtered by an artificial kidney machine in aprocess called dialysis (di AL uh sus). During dialysis, bloodfrom an artery is pumped through tubing that is bathed in asalt solution similar to blood plasma. Waste materials diffusefrom the tube containing blood and are washed away by thesalt solution. The cleaned blood is returned to a vein. A per-son with only one kidney can still function normally. Analternative dialysis treatment is pictured in Figure 19-16.

The urinary system is a purifying unit for the circulatorysystem. Wastes are filtered from blood as it passes throughthe kidneys. Some water, salts, and nutrients are reabsorbedto maintain homeostasis. Waste materials, dissolved inwater, are eliminated from the body. This systemhelps to maintain the health of cells and,therefore, the entire body.

✔

1. Describe the functions of the urinary system.2. Explain how the kidneys remove wastes and keep

fluids and salts in balance.3. Compare the excretory and urinary systems.4. Think Critically: Explain why reabsorption of cer-

tain materials in the kidneys is important.

5. Skill BuilderConcept Mapping Using a network

tree concept map, compare the excretory functions of the kidneys and the lungs. If you need help, refer to Concept Mapping in the Skill Handbook on page 678.


5 liters per 5 minutes � 1 literper minute rate of flow

CHAPTER 19 REVIEWING MAIN IDEAS 541

✔Reading Check

What probable outcome

could you predict for a

young person who

begins smoking? What

is the basis for your

prediction?

Section

19-2 THE EXCRETORY SYSTEM

Your urinary system is made up of organs thatrid your blood of wastes produced by the metabolism ofnutrients. It also controls blood volume by removingexcess water produced by body cells. Kidneys are themajor organs of the urinary system. They filter wastesfrom your body and keep sodium, water, and other chemicals in balance. When kidneys fail to work, dialysis may be used. In addition to the urinary system, parts ofthe digestive, circulatory, and respiratory systems worktogether as the excretory system. How do the kidneysmaintain homeostasis?

DR. BENJAMIN CARSON, SURGEON

Dr. Benjamin Carson is a surgeon at JohnsHopkins Hospital. Dr. Carson says that operating on a patient islike if you were a tightrope walker: If you are experienced, walk-ing the rope isn’t frightening, but if you haven’t done it before, it can be scary. Dr. Carson admits that operating is sometimestaxing—especially when you do it for 16 hours at a stretch. Dr.Carson encourages young people to ask themselves, “What haveI always been good at?” and to ask other people what they seethat you’re good at. What problems of the respiratory sys-tem and excretory system could require surgery?

CareerCONNECTION

CHAPTER 19 REVIEWING MAIN IDEAS 541

Answers to Questions

Section 19-1The Respiratory System Thetrachea must remain open forair to enter through it; theesophagus is soft and doesnot need to be open exceptwhen food is movingthrough.Diseases and DisordersLung cancer is the third lead-ing cause of death in theUnited States.

Section 19-2The Excretory System Thekidneys filter water, sugar,salt, and wastes from blood.Then most water, sugar, andsalt is reabsorbed.

Portfolio Encourage students to place intheir portfolios one or two items of whatthey consider to be their best work. Exam-ples include: • Using Math, p. 528• Activity 19-1, pp. 530–531• MiniLab, p. 535

Performance Additional performance as-sessments may be found in PerformanceAssessment and Science Integration Ac-tivities. Performance Task Assessment Listsand rubrics for evaluating these activitiescan be found in Glencoe’s Performance As-sessment in the Science Classroom.

P

Assessment

CD-ROMGlencoe Science VoyagesInteractive CD-ROMChapter Summaries and QuizzesHave students read theChapter Summary then take theChapter Quiz to determinewhether they have masteredchapter content.

CareerCONNECTION

Problems will vary. Possibleproblems could include re-moving lung cancer cells, kid-ney transplants, and openingblocked nasal passages ofchronic sinusitis.

Chapter

19ReviewingMain Ideas

For a preview of thischapter, study this

Reviewing Main Ideasbefore you read the chapter.After you have studied thischapter, you can use theReviewing Main Ideas toreview the chapter.

The GlencoeMindJogger,Audiocassettes,and CD-ROM

provide additionalopportunities for review.

Chapter Reviewing Main IdeasChapter Reviewing Main Ideas19

DISEASES AND DISORDERS

Many serious respiratory problems are related to smok-ing. In addition to smoking, polluted air and coal dustalso have been associated with diseases such aschronic bronchitis, emphysema, lung cancer, andasthma. Which respiratory disease is the thirdleading cause of death in men and women in theUnited States?


Section

19-1 THE RESPIRATORY SYSTEM

Your respiratory system helps take oxygen intoyour lungs and body cells and helps you remove carbondioxide. Inhaled air passes through the nasal cavity,pharynx, larynx, trachea, bronchi, and bronchiolesand into the alveoli of the lungs. The mechanism ofbreathing results in part from the diaphragm’s move-ment, which changes the pressure within the lungs. Why does the trachea have cartilage but the esophagus does not?


Reviewing Main Ideas canbe used to preview, review,reteach, and condense chap-ter content.

Preview

Linguistic Have stu-dents try to answer the

questions in their ScienceJournals. Use student an-swers as a source for discus-sion throughout the chapter.

Review

Interpersonal Havestudents answer the

questions on separate piecesof paper and compare theiranswers with those of otherstudents in the class.

Reteach

Visual-Spatial Havestudents look at the il-

lustrations on these pages.Ask them to describe detailsthat support the main ideas ofthe chapter found in the state-ment for each illustration.

Auditory-Musical If

time does not permit

teaching the entire chap-

ter, use the information on

these pages along with the

chapter Audiocassettes to

present the material in a

condensed format.

OUT OF

TIME?

Living at High Altitudes People wholive at high altitudes must deal with a slightlyreduced pull of gravity, gas molecules thatspread out in the air, and a reduced pressuregradient. Have students research how thebodies of people native to high altitudeshave adapted to these changes.

Cultural DiversityCultural Diversity

TEST-TAKING

CHAPTER 19 ASSESSMENT 543

Test-Taking Tip

Survey the Surroundings Find outwhat the conditions will be for takingthe test. Will the test be timed? Will you be allowed to take a break? Knowthese things in advance so that you canpractice taking tests under the same conditions.

Test Practice

Use these questions to test your Science Proficiency.

1. Air inhaled through the nose is filtered,warmed, and moistened. What are somebenefits of these actions?A) The process prevents nitrogen

and carbon dioxide from reaching the lungs.

B) The process prevents bad odors fromreaching the trachea and bronchi.

C) The process prevents drying out ofpassageways and traps foreign materials.

D) The process prevents the formation ofmucus and cilia in the nasal cavity.

2. Blood flowing through the kidneys is fil-tered to remove excess materials andwastes. Which of the following are themajor substances removed?A) salts, sugar, water, and wastesB) water, salt, sugar, and urineC) carbon dioxide, salt, sugar,

and wastesD) water, salts, oxygen, and wastes

Developing Skills

If you need help, refer to the Skill Handbook.

21. Making and Using Graphs: Make a circle graph of total lung capacity.• Tidal volume (inhaled or exhaled

during a normal breath) � 500 mL• Inspiratory reserve volume (air that

can be inhaled forcefully after a nor-mal inhalation) � 3000 mL

• Expiratory reserve volume (air thatcan be exhaled forcefully after a nor-mal expiration) � 1100 mL

• Residual volume (air left in the lungsafter forceful exhalation) � 1200 mL

22. Interpreting Data: Interpret the databelow. How much of each substance is reabsorbed into the blood in the kidneys? What substance is totallyexcreted in the urine?

23. Recognizing Cause and Effect: Discusshow lack of oxygen is related to lack ofenergy.

24. Hypothesizing: Hypothesize the num-ber of breaths you would expect a per-son to take per minute in each situationand give a reason for each hypothesis.

• while sleeping

• while exercising

• while on top of Mount Everest

Amount moving Amountthrough kidney excreted

Substance to be filtered in urine

water 125 L 1 L

salt 350 g 10 g

urea 1 g 1 g

glucose 50 g 0 g

Materials Filtered by the Kidneys

AssessmentAssessment

CHAPTER 19 ASSESSMENT 543

The Test-Taking Tip waswritten by The Princeton Re-view, the nation’s leader intest preparation.

1. C2. A

Developing Skills

21. The circle graph shouldshow tidal volume occu-pying 31° of the circle; in-spiratory reserve volume,186°; expiratory reservevolume, 68°; and residualvolume, 74°.

22. water—124 L; salt—340 g;urea—all is excreted; glu-cose—50 g

23. Cells need oxygen tobreak down food to re-lease energy. If oxygenisn’t supplied, energy isnot released.

24. Number of breaths whilesleeping is low becauseless oxygen is needed forrest. While exercising,breaths per minute in-crease to get oxygen tothe muscles. On top ofMount Everest there isless total oxygen present;thus, more breaths perminute are taken.

Bonus Question

What happens to the dis-solved nutrients in the bloodthat pass through the kid-neys? They are filtered, but re-turn to the blood.

Test Practice

The Test Practice Workbook provides studentswith practice in the format, concepts, and criti-cal-thinking skills tested in standardized exams.

Reproducible MastersChapter Review, pp. 37–38Performance Assessment, p. 19Assessment, pp. 73–76

Glencoe Technology

Chapter Review Software

Computer Test Bank

MindJogger Videoquiz

L2

L2

L2

Assessment Resources

Chapter

19Assessment Chapter AssessmentChapter Assessment19


9. When you exhale, which way does therib cage move?A) It moves up. C) It moves out.B) It moves down. D) It stays the same.

10. Which of the following is a lung disorderthat may occur as an allergic reaction?A) asthma C) emphysemaB) chronic D) cancer

bronchitis11. Which of the following conditions does

smoking worsen?A) arthritis C) excretionB) respiration D) emphysema

12. Which of the following are filtering unitsof the kidneys?A) nephrons C) neuronsB) ureters D) alveoli

13. Urine is temporarily held in which of thefollowing structures?A) kidneys C) ureterB) bladder D) urethra

14. Through which of the following isapproximately 1 L of water lost per day?A) sweat C) urineB) lungs D) none of these

15. Which of the following substances isNOT reabsorbed by blood after it passesthrough the kidneys?A) salt C) wastesB) sugar D) water

Thinking Critically

16. Compare air pressure in the lungs during inhalation and exhalation.

17. What is the advantage of the lungs having many air sacs instead of beingjust two large sacs, like balloons?

18. Explain the damage smoking does to cilia, alveoli, and lungs.

19. What would happen to the blood if the kidneys stopped working?

20. Explain why a large kidney stone isoften painful.

a. alveolib. asthmac. bladderd. bronchie. chronic

bronchitisf. diaphragmg. emphysemah. kidney

i. larynxj. nephronk. pharynxl. trachea

m. uretern. urethrao. urinary systemp. urine

Using the list above, replace the underlinedwords with the correct Vocabulary term.

1. At the lower end of the tubelike passage-way for both food and air is a flap of tissue called the epiglottis.

2. At the lower end of the trachea are twoshort branches that carry air into thelungs.

3. Each kidney is made up of about 1 mil-lion tiny filtering units.

4. An elastic, muscular organ holds urineuntil it leaves the body.

5. A tube carries urine from the bladder tothe outside of the body.

Checking Concepts

Choose the word or phrase that best answersthe question.

6. When you inhale, which of the followingcontracts and moves down?A) bronchioles C) nephronsB) diaphragm D) kidneys

7. Air is moistened, filtered, and warmedin which of the following structures?A) larynx C) nasal cavityB) pharynx D) trachea

8. Exchange of gases occurs between capillaries and which of the followingstructures?A) alveoli C) bronchiolesB) bronchi D) trachea

Using Vocabulary


Using Vocabulary

1. l2. d3. j4. c5. n

To reinforcechapter vo-

cabulary, use the Study Guidefor Content Mastery booklet.Also available are activities forGlencoe Science Voyages onthe Glencoe Science Web Site.www.glencoe.com/sec/science/ca

Checking Concepts

6. B 11. D7. C 12. A8. A 13. B9. B 14. C

10. A 15. C

Thinking Critically

16. When you inhale, the vol-ume of your chest cavityincreases. Air pressure isreduced in your chestcavity, and your lungs fillwith air. When you ex-hale, the size of yourchest cavity decreases.Pressure in your lungs in-creases and you breatheout.

17. Having many air sacs in-creases the surface areafor gas exchange.

18. Cilia are destroyed andtherefore cannot moveparticles out of the lungs;alveoli lose elasticity, de-creasing total surface areaof the lungs available forgas exchange; carcino-gens cause the growth ofcancerous cells in lungtissue.

19. If the kidneys stopped working, bloodwould accumulate the waste productsof the body’s organs. It would becomepoisonous, and the person would needimmediate medical care.

20. Kidney stones in the ureter extend andblock the tube and cause severe pain. In-fections may also occur.


Documents

Chapter 19: Respiration and Excretion - mrwrightsclass.netmrwrightsclass.net/resources/old-7th-grade-text/chap19.pdf · The Excretory System 2 Sessions 1 Block 1. ... one positive