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BIO 212 FINAL EXAM QUESTIONS WITH
DETAILED VERIFIED ANSWERS
At an atmospheric pressure of 870 mm Hg with 21 percent oxygen, the
partial pressure of oxygen is _____.
A) 219 mm Hg
B) 127 mm Hg
C) 151 mm Hg
D) 182 mm Hg
E) 100 mm Hg Ans: D
At the summit of a high mountain, the atmospheric pressure is 380 mm
Hg. If the atmosphere is still composed of 21percent oxygen, then the
partial pressure of oxygen at this altitude is about _____.
A) 80 mm Hg
B) 160 mm Hg
C) 0 mm Hg
D) 380 mm Hg
E) 760 mm Hg Ans: A
The sun shining on a tidal pool during a hot day heats the water. As some
water evaporates, the pool becomes saltier, causing _____.
A) an increase in its ability to sustain aerobic organisms
B) a decrease in its oxygen content
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C) a decrease in the water's density
D) an increase in its carbon dioxide content Ans: B
A rabbit taken from a meadow near sea level and moved to a meadow
high on a mountainside would have some trouble breathing. Why?
A) The percentage of oxygen in the air at high elevations is higher than
at sea level.
B) The partial pressure of oxygen in the air at high elevations is lower
than at sea level.
C) The percentage of oxygen in the air at high elevations is lower than at
sea level.
D) The partial pressure of oxygen in the air at high elevations is higher
than at sea level. Ans: B
Determine the rate of diffusion in the gas-exchange organ of an air-
breathing animal where the area for gas exchange in the lung is 200
mm2, the diffusion constant is 0.08, the PO2 (partial pressure of oxygen)
of the air in the lung is 140 mm Hg, the PO2 in blood flowing into the
lung is 90 mmHg, and the thickness of the gas exchange membrane is
0.001 mm.
A) 125
B) 800,000
C) 10,000,000
D) 00032 Ans: B
Some animals have no gills when young, but then develop gills that grow
larger as the animal grows larger. What is the reason for this increase in
gill size?
A) Relative to their volume, the young have more surface area across
which they can transport all the oxygen they need.
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B) The young have a higher basal metabolic rate.
C) The young of these animals are much more active than the adult,
which leads to a higher BMR (basal metabolic rate) and, therefore, a
higher need for oxygen.
D) Relative to their surface area, the young have more body volume in
which they can store oxygen for long periods of time. Ans: A
Carbon dioxide levels in the blood and cerebrospinal fluid affect pH. This
enables the organism to sense a disturbance in gas levels as _____.
A) the medulla oblongata is able to control the concentration of
bicarbonate ions in the blood
B) the brain directly measures and monitors oxygen levels and causes
breathing changes accordingly
C) the medulla oblongata, which is in contact with cerebrospinal fluid,
monitors pH and uses this measure to control breathing
D) stretch receptors in the lungs cause the medulla oblongata to speed
up or slow breathing
E) the brain alters the pH of the cerebrospinal fluid to force the animal to
retain more or less carbon dioxide Ans: C
When you are jogging, your muscles are using more oxygen and
releasing more carbon dioxide into the blood than when you are at home
on the couch. Which of the following would occur during your jog?
A) The concentration of bicarbonate ions (HCO3-) in the blood would
decrease.
B) The volume of the dead air space would decrease.
C) Blood pH would become more basic.
D) The medullary respiratory center would detect rising carbon dioxide
levels. Ans: D
BIO 212 FINAL EXAM QUESTIONS WITH
DETAILED VERIFIED ANSWERS
At an atmospheric pressure of 870 mm Hg with 21 percent oxygen, the
partial pressure of oxygen is _____.
A) 219 mm Hg
B) 127 mm Hg
C) 151 mm Hg
D) 182 mm Hg
E) 100 mm Hg Ans: D
At the summit of a high mountain, the atmospheric pressure is 380 mm
Hg. If the atmosphere is still composed of 21percent oxygen, then the
partial pressure of oxygen at this altitude is about _____.
A) 80 mm Hg
B) 160 mm Hg
C) 0 mm Hg
D) 380 mm Hg
E) 760 mm Hg Ans: A
The sun shining on a tidal pool during a hot day heats the water. As some
water evaporates, the pool becomes saltier, causing _____.
A) an increase in its ability to sustain aerobic organisms
B) a decrease in its oxygen content
, Page | 2
C) a decrease in the water's density
D) an increase in its carbon dioxide content Ans: B
A rabbit taken from a meadow near sea level and moved to a meadow
high on a mountainside would have some trouble breathing. Why?
A) The percentage of oxygen in the air at high elevations is higher than
at sea level.
B) The partial pressure of oxygen in the air at high elevations is lower
than at sea level.
C) The percentage of oxygen in the air at high elevations is lower than at
sea level.
D) The partial pressure of oxygen in the air at high elevations is higher
than at sea level. Ans: B
Determine the rate of diffusion in the gas-exchange organ of an air-
breathing animal where the area for gas exchange in the lung is 200
mm2, the diffusion constant is 0.08, the PO2 (partial pressure of oxygen)
of the air in the lung is 140 mm Hg, the PO2 in blood flowing into the
lung is 90 mmHg, and the thickness of the gas exchange membrane is
0.001 mm.
A) 125
B) 800,000
C) 10,000,000
D) 00032 Ans: B
Some animals have no gills when young, but then develop gills that grow
larger as the animal grows larger. What is the reason for this increase in
gill size?
A) Relative to their volume, the young have more surface area across
which they can transport all the oxygen they need.
, Page | 3
B) The young have a higher basal metabolic rate.
C) The young of these animals are much more active than the adult,
which leads to a higher BMR (basal metabolic rate) and, therefore, a
higher need for oxygen.
D) Relative to their surface area, the young have more body volume in
which they can store oxygen for long periods of time. Ans: A
Carbon dioxide levels in the blood and cerebrospinal fluid affect pH. This
enables the organism to sense a disturbance in gas levels as _____.
A) the medulla oblongata is able to control the concentration of
bicarbonate ions in the blood
B) the brain directly measures and monitors oxygen levels and causes
breathing changes accordingly
C) the medulla oblongata, which is in contact with cerebrospinal fluid,
monitors pH and uses this measure to control breathing
D) stretch receptors in the lungs cause the medulla oblongata to speed
up or slow breathing
E) the brain alters the pH of the cerebrospinal fluid to force the animal to
retain more or less carbon dioxide Ans: C
When you are jogging, your muscles are using more oxygen and
releasing more carbon dioxide into the blood than when you are at home
on the couch. Which of the following would occur during your jog?
A) The concentration of bicarbonate ions (HCO3-) in the blood would
decrease.
B) The volume of the dead air space would decrease.
C) Blood pH would become more basic.
D) The medullary respiratory center would detect rising carbon dioxide
levels. Ans: D
