Answer Key
CHAPTER 16: RESPIRATION AND
EXCRETION
16-1 What is the respiratory system?
Lesson Review
1. d 2. e 3. a 4. c 5. g 6. b 7. f
Skill Challenge
1. nasal cavity 2. nose 3. mouth 4. throat
5. epiglottis 6. larynx 7. trachea 8. bronchus
9. right lung 10. left lung (or alveoli)
16-1 What is the respiratory system?
Enrichment Activity: Comparing the Pathways of
Food and Air
PART A
1. also called the throat; passageway for both food
and air 2. connects the mouth to the stomach;
passageway for food located at the base of the
pharynx 3. also called the windpipe; passageway
that carries air from the throat to the bronchi 4. flap
of tissue that covers the top of the trachea;
passageway for air that closes off the top of the
throat during swallowing to prevent food from
entering 5. respiratory and digestive 6. epiglottis
7. It is covering the top of the trachea. 8. Food can
get past the epiglottis and into the windpipe,
causing a person to choke.
PART B
1. esophagus 2. epiglottis 3. pharynx 4. trachea
16-2 What are breathing and
respiration?
Lesson Review
1. inhaling 2. exhaling 3. respiration 4. chemical
5. mechanical 6. diaphragm 7. cellular 8. larger
9. smaller 10. external
Skill Challenge
1. a. exhaling b. Possible answer: The diaphragm
has moved upward, toward the lungs. The space
inside the chest is smaller. 2. a. inhaling b. Possible
answer: The diaphragm has moved downward,
away from the lungs. The space inside the chest is
larger.
16-3 What happens to air before it
reaches the lungs?
Lesson Review
1. tiny hairlike structures 2. to push mucus and
trapped particles toward the back of the throat
3. Cilia are located in the lining of the windpipe and
nose. 4. a sticky liquid that traps dirt, dust, and
bacteria in the windpipe and nose 5. to trap dirt,
dust, and bacteria before such harmful particles
enter the lungs, and to keep respiratory tissue moist
6. in the nose and windpipe 7. Air is filtered,
moistened, and warmed before it reaches the lungs.
8. Moistened air helps to keep the respiratory tissues
from drying out and helps prevent damage to the
lungs.
Skill Challenge
1. Hairs in the nose: to filter particles from the air
2. Cilia in the trachea: to filter air and push mucus
toward the back of the throat 3. Cells lining the
nose: to produce mucus
16-4 How does oxygen get into the
blood?
Lesson Review
1. gases 2. nitrogen 3. cellular respiration
4. grapes 5. alveoli 6. capillaries 7. red blood cells
8. carbon dioxide 9. oxygen 10. carbon dioxide
Skill Challenge
Description: Oxygen is moving from the alveoli into
the capillaries. Capillaries carry the oxygen to all the
cells of the body. Carbon dioxide is moving from the
capillaries into the lungs. The carbon dioxide is
released from the body when the lungs exhale.
Concepts and Challenges in Life Science, Teacher’s Resources CD-ROM
(c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved.
Respiration and Excretion: CHAPTER 16
Answer Key
16-5 How does tobacco affect the body?
16-6 What is the excretory system?
Lesson Review
1. 100 2. stimulant 3. monoxide 4. cilia 5. heart
6. narrower 7. emphysema
Skill Challenge
Surgeon General's Warnings: Accept any three of
the following: Smoking Causes Lung Cancer, Heart
Disease, Emphysema, and May Complicate
Pregnancy. Quitting Smoking Now Greatly Reduces
Serious Risks to Your Health. Smoking By Pregnant
Women May Result in Fetal Injury, Premature Birth,
and Low Birth Weight. Cigarette Smoke Contains
Carbon Monoxide. Diseases: Accept any three of
the following: lung cancer, emphysema, coronary
heart disease, bronchitis, bladder cancer,
periodontitis, mouth cancer, and throat cancer.
Lesson Review
1. true 2. gets rid of 3. true 4. true 5. excretory
6. kidneys 7. true 8. large 9. true 10. liquid
11. true 12. urethra
Skill Challenge
1. skin 2. lungs 3. kidneys 4. bladder
16-5 How does tobacco affect the body?
Enrichment Activity: Health Trends
Check students’ graphs for accuracy.
16-7 How do the kidneys work?
Lesson Review
1. to remove wastes from blood 2. urine 3. urea
4. water, salts, and urea 5. urethra 6. waste
products of proteins 7. in the collecting tube
8. nutrients the body needs 9. the filtering
structures of the kidneys 10. After blood enters the
nephrons, water, salts, and urea are forced out of the
capillaries and into Bowman’s capsule where they
remain in the collecting tube. Nutrients pass back
into the blood and the filtered blood returns to the
heart.
Skill Challenge
1. kidneys 2. ureter 3. bladder 4. urethra 5. to
remove waste products from the blood 6. to carry
urine from the kidneys to the bladder 7. to store
urine until it is removed from the body 8. to carry
urine to the outside of the body
16-8 How does the skin remove wastes?
1. The number of male smokers has steadily
decreased since 1970. 2. The number of female
smokers has steadily decreased since 1970.
3. Possible answers: the warnings issued by the
surgeon general relating cigarette smoking and
cancer, as well as increased public knowledge about
the effect of cigarette smoking on the body. 4. New
anti-smoking campaigns may help to decrease the
number of smokers even more. Also, new legislation
that bans cigarette advertising that is aimed towards
teens may also help to lower the number of people
who start smoking.
Lesson Review
1. dermis 2. epidermis 3. pores 4. dead 5. hair
follicles 6. oil glands 7. dermis 8. capillaries
9. sweat glands 10. perspiration
Skill Challenge
1. hair 2. pore 3. oil gland 4. sweat gland 5. hair
follicle 6. blood vessels
16-8 How does the skin remove wastes?
Enrichment Activity: Comparing the Dermis and
the Epidermis
1. Dermis 2. Dermis 3. Epidermis 4. Dermis
5. Epidermis 6. Epidermis 7. Epidermis
8. Epidermis 9. Dermis 10. Dermis 11. Epidermis
12. Epidermis 13. Epidermis 14. Dermis
15. Dermis 16. Dermis 17. Dermis 18. Dermis
19. Epidermis 20. Epidermis
Concepts and Challenges in Life Science, Teacher’s Resources CD-ROM
(c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved.
Respiration and Excretion: CHAPTER 16
Answer Key
The Big Idea
Lesson Review
1. a condition that occurs when the body is heated
beyond the control of normal systems 2. Rapid
breathing decreases carbon dioxide in the blood,
increases oxygen in the blood, and slightly cools the
body. 3. Heat stroke occurs when body systems
cannot reverse overheating and the sweating system
shuts down. Body temperature continues to rise and
body systems shut down one at a time.
Skill Challenge
1. Athletes are encourage to drink plenty of fluids
before, during, and after exercise to prevent
dehydration and overheating. 2. Dogs do not have
sweat glands in their skin. They pant to get rid of
carbon dioxide and to cool their bodies. 3. If it is
not possible to go inside, sit down in the shade and
drink water. Wet your skin with water or a wet
cloth, and sit in a breeze or fan yourself.
CHAPTER 16: RESPIRATION AND
EXCRETION
Key Term Review
Across
4. urine 5. perspiration 7. urea 8. evaporation
9. pores 11. excretion 12. inhale 13. alveoli
Down
1. mucus 2. diaphragm 3. bronchi 6. respiration
10. cilia 11. exhale
Concepts and Challenges in Life Science, Teacher’s Resources CD-ROM
(c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved.
Respiration and Excretion: CHAPTER 16