The Respiratory System
Lungs and Breathing
The following statements trace the path of oxygen from the atmosphere to a body cell. Label
each statement from 1 – 6 in the correct sequence. Not all steps are listed here.
_____ 1.
Passes through the bronchi.
_____ 2.
Passes through the bronchioles.
_____ 3.
Enters the body through the mouth or nasal cavity.
_____ 4.
Blood in the capillaries of alveoli picks up oxygen and releases carbon dioxide
_____ 5.
Arrives at the alveolus and diffuses into the blood.
_____ 6.
Is carried by the blood to tissue cells.
Gas Exchange
Mark each statement below T if it is true and F if it is false.
_____ 7.
Gas exchange occurs when oxygen in the alveoli diffuses into the blood in the
capillaries and carbon dioxide in the blood diffuses into the air of the alveoli.
_____ 8.
Carbon dioxide can be eliminated from cells by diffusion.
_____ 9.
Oxygen is transported in the blood by hemoglobin.
Regulation of Breathing
Complete each statement by underlining the correct word or phrase in the brackets.
10.
Receptors in the (spinal cord and lymphatic system/brain and circulatory system) enable
the body to automatically regulate oxygen and carbon dioxide concentrations by sending
signals to the brain.
11.
The concentration of carbon dioxide in the blood has a (greater/lesser) effect on the
regulation of breathing than does the concentration of oxygen.
12.
Diffusion of gases between the blood or tissue fluids and cells is called
(external respiration / internal respiration / cellular respiration).
13.
Release of energy from the breakdown of glucose to form ATP is called
(external respiration / internal respiration / cellular respiration).
14.
Exchange of gases between the atmosphere and blood is called
(external respiration / internal respiration / cellular respiration).
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Place a check next to each statement that accurately describes the operation of the
diaphragm and chest muscles.
_____ 15.
When the muscles of the diaphragm and the external intercostal muscles contract,
the chest cavity expands.
_____ 16.
When the diaphragm contracts, the lungs collapse.
_____ 17.
When the diaphragm relaxes, the pressure inside the chest cavity increases and
air rushes out.
Diseases of the Respiratory System
Compare three diseases of the respiratory system by describing the disease.
18. Asthma ___________________________________________________________________
______________________________________________________________________________
19. Emphysema ________________________________________________________________
______________________________________________________________________________
20. Lung Cancer _______________________________________________________________
______________________________________________________________________________
THE RESPIRATORY SYSTEM REVIEW
1. What is oxygen needed for? aerobic cellular respiration
What is the function of this process? to make ATP
2. For animals, what gas needs to be taken in? oxygen
What gas is a waste product? carbon dioxide
3. Where does air enter the body? mouth and nose
Where does it travel to? alveoli
4. What is another name for the voice box? larynx
5. What is another name for the windpipe? trachea
6. What do the tissues that line the larynx and trachea do? trap unwanted particles in the
respiratory tract
7. Explain what the bronchioles are. small branches from the bronchi
8. What are the bronchioles lined with? cilia
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What do you suppose is the purpose of these? move trapped particles out of the respiratory of the
respiratory tract
9. Define alveoli (include what gases do in them). small air sacs where gases are exchanged with
capillaries
10. Describe the function of the capillaries around the alveolus. allow blood to exchange gases
with alveoli
11. How many alveoli does each lung contain? about 300 million alveoli per lung
What is the total surface area for each lung? about 70-90 square meters per lung; the surface area
of both lungs together is almost the size of a tennis court!
12. When a person inhales, explain what happens to the diaphragm. it contracts and pulls down
13. When a person exhales, explain what happens to the diaphragm. it relaxes and goes up
14. How does the size of the chest cavity change when a person inhales? it gets bigger
15. How does the size of the chest cavity change when a person exhales? it’s smaller than on an
inhale
16. What process is used for gas to go from the alveoli to the capillaries? diffusion!!
17. How does carbon dioxide get out of blood? it diffuses from a high concentration to a lower
concentration
18. What does oxygen bind to in the blood? hemoglobin
19. What is hemoglobin? a protein found in red blood cells
20. Where does the oxygen go to from the red blood cells? into tissues that need oxygen (this
could be muscle cells, brain cells, skin cells, etc.
21. What does your body’s tissues use oxygen for? to make ATP through cellular respiration
22. Explain the following respiratory diseases:
Carbon Monoxide Poisoning - suffocation occurs when Carbon Monoxide gas blocks O2 from
binding to hemoglobin; Carbon Monoxide is given off from natural gas (the stove), car fumes,
etc.
Tuberculosis – a contagious disease transmitted by airborne particles; most people are vaccinated
against TB
Cystic Fibrosis – a genetic disease that causes excess mucus to build up in respiratory passages
and other organs; afflicted children often need a machine to help remove excess mucus from
breathing passages
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The Excretory System
Kidney Form and Function
On the line at the left, write the letter of the answer that best completes each sentence.
______ 1.
Ammonia and other nitrogen-containing wastes are eliminated from the human
body in the form of
a.
feces.
b.
uric acid.
c.
urea.
d.
purine.
______ 2.
Each human kidney contains over 1 million ________ that serves as bloodcleaning units.
a.
stones
b.
microvillus
c.
enzymes
d.
nephrons
Urine Formation
Mark each statement below T if it is true and F if it is false.
______ 3.
The first state of urine formation is called titration.
______ 4.
About 1 L of urine is produced each day.
______ 5.
During reabsorption, water and solutes moved out of the nephron and are sent
back into the bloodstream.
______ 6.
Urine exits the body through the ureter, a tube that leads outside the body.
Kidney Disorders and Treatment
Complete each statement by writing the correct word in each space provided.
7. The common kidney disorder _____________ ___________ are deposits of uric acid,
calcium salts, and other substances.
8. Kidney stones may be eliminated naturally from the body or be removed by
____________________ procedures.
9. Patients with kidney disorders may have their blood artificially filtered by ______________.
10. Why does the liver convert ammonia into urea? ___________________________________.
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Write the name of the structure in the excretory system next to its description.
Bowman’s capsule
Nephron
Urethra
Glomerulus
Ureter
Urinary bladder
________________________________
11. Basic functional unit of work in the kidney.
________________________________
12. Tube that connects the renal pelvis to the
bladder.
_________________________________
13. Holds urine.
_________________________________
14. Tube from the bladder to the outside of
the body.
__________________________________
15. Cup-shaped end of the renal tubule that
surrounds the glomerulus.
___________________________________ 16. Mass of capillaries in the nephron through
which blood flows at high pressure.
17. What type of environment are your respiratory and excretory system trying to create in your
body?
The body is trying to maintain a balanced internal environment (homeostasis) by eliminating
waste products.
18. What are the waste products from human metabolism? The excretory system produces urea
as a waste product. The respiratory system produces carbon dioxide as a waste product.
19. Ammonia is a poisonous waste product that is created from breaking down excess amino
acids. What is ammonia converted to, to make it less toxic and where does this take place?
It’s converted to urea in the liver.
20. How is urea eliminated from the body? It’s filtered out by the kidneys and eliminated from
the body in urine.
21. Why does your perspiration have an odor? Because it may contain urea.
22. What organ is the main part of the excretory system? kidney
23. What material is filtered out of the capillaries (glomerulus) into the Bowman’s capsule and
removed from the blood? Basically all small components of the blood are filtered out
(water, glucose, amino acids, urea, etc.) The good stuff is reabsorbed and the bad stuff (urea)
forms the urine.
THE EXCRETORY SYSTEM REVIEW
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1. What product is released from the breakdown of amino acids? ammonia
2. Why must ammonia be released from the body? it is toxic to cells
3. What makes urea? ammonia is combined with carbon dioxide in the liver
4. Is urea more or less toxic than ammonia? less
5. What does urea enter after it has been in the liver? the blood
6. How does some of the urea leave the body? sweat
7. What is perspiration made up of? water, urea, salts
8. How is most urea eliminated from the body? in the urine
9. How big are the kidneys and where are the kidneys located? about the size of your fists; they
are located in your lower back
10. What are nephrons? tiny filtration units of the kidney
11. How many nephrons does each kidney have? about 1 million
12. What does the capsule of a nephron surround? blood vessels
13. What does the blood in the capillaries do? transport blood cells and other materials
14. After the substances twist and turn around in the nephron, what do they form? eventually
urine is formed as a waste product
15. What does urine contain? mostly water and urine, some salts and hydrogen ions too
16. What is the first stage of urine formation called? filtration
17. What happens during filtration? all small substances are filtered out of the blood
18. What substances remain in the blood? large particles like blood cells and big proteins
19. What substances are filtered out of the blood? all small substances are filtered out of the
blood
20. What makes the concentrations of urine vary? your level of hydration
21. What is the second stage of urine formation? reabsorption
22. What percentage of filtered blood is sent back into the bloodstream? 99%
23. Again, list the substances that are sent back to the bloodstream. glucose, amino acids, water,
some salts and minerals
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24. What controls water reabsorption? the hypothalamus
25. What hormone is involved in this process? ADH (anti-diuretic hormone)
26. When your body needs to save water, what happens to the amount of this hormone?
the amount of ADH increases
27. What does ADH do to the ends of the nephron? it makes the ends of the nephrons more
permeable to water so more water is reabsorbed and conserved in the body
28. Is urine more or less dilute with a decrease in ADH? more dilute
29. After reabsorption, where is the urine located? in the collecting ducts of the nephrons
30. What is the urine made up of? water, urea, salts
31. After the kidney, where does the urine flow? the ureter
32. After the above tube, where does the urine flow next? bladder
33. Through which tube does the urine leave the body? urethra
34. Where does this tube lead? out of the body
Congratulations, you’ve made it to the end of this answer key. 
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