RESPIRATORY PHYSIOLOGY EXAM
WITH CORRECT ANSWERS
, lOMoARcPSD|52690394
MCQs RESPIRATORY PHYSIOLOGY
RESPIRATORY PHYSIOLOGY
1. The partial pressure of oxygen in dry air inhaled by divers at a depth of 100 feet (4 atm) below
sea level is approximately
a. 160mmHg
b. 320mmHg
c. 640mmHg
d. 1280mmHg
e. none of the above
2. Two healthy women with identical tidal volumes are subjected to spirometry and blood gas
measurements. Subject A doubles her tidal volume and decreases her respiratory rate to ½
of baseline. Subject B decreases her tidal volume to ½ of baseline and doubles her
respiratory rate. Which of the following statements about the resulting alveolar ventilation
in the two women is true?
a. Alveolar ventilation is unchanged in both subjects
b. Alveolar ventilation increases in both subjects
c. Alveolar ventilation decreases in both subjects
d. Alveolar ventilation increases in subject A and decreases in subject B
e. Alveolar ventilation decreases in subject A and increases in subject B
3. Increased baroreceptor discharge acts via the medulla to
a. heart rate
b. stroke volume
c. vessel diameter
d. BP
e. renin secretion
4. A man breathing room air at sea level has an alveolar ventilation of 2L/min. The blood gases
show a PaCO2 of 48mmHg and a PaO2 of 70mmHg. The alveolar oxygen tension (PaO2 ) is
a. 150mmHg
b. 110mmHg
c. 100mmHg
d. 90mmHg
e. 60mmHg
5. Reduction of functional Hb associated with anaemia, met Hb, or CO poisoning does not produce
hyperpnoea because the
a. Blood flow to the carotid body is
b. Total arterial O2 content is maintained within normal range
c. Carotid body chemoreceptors are stimulated
d. Central chemoreceptors are stimulated
1
, lOMoARcPSD|52690394
MCQs RESPIRATORY PHYSIOLOGY
e. pO2 of arterial blood is normal
6. During a normal inspiration, more air goes to the alveoli at the base of the lung than to the
alveoli at the apex of the lung because
a. The alveoli at the base of the lung have more surfactant
b. The alveoli at the base of the lung are more compliant
c. The alveoli at the base of the lung have higher V/Q ratios
d. There is a more negative intra pleural pressure at the base of the lung
e. There is more blood flow to the base of the lung
7. The activity of the central chemoreceptors is stimulated by
a. An increase in the pCO2 of blood flowing through the brain
b. A decrease in the pO2 of blood flowing through the brain
c. A decrease in the oxygen content of blood flowing through the brain
d. A decrease in the metabolic rate of the surrounding brain tissue
e. An increase in the pH of the CSF
8. Metabolic functions of the lung include all of the following EXCEPT
a. Inactivation of bradykinin
b. Inactivation of prostaglandins
c. Inactivation of angiotensin II
d. Synthesis of prostaglandins
e. Synthesis of surfactant
9. Regarding V/Q differences in the lung
a. In healthy individuals, anatomic dead space is less than physiologic dead space
b. The relative change in blood flow from apex to base is less than relative change in ventilation
c. Ventilation/perfusion differences are due to gravity
d. Ventilation/perfusion ratio is low at the base
e. All of the above
10. A spirometer can be used to measure directly
a. Functional residual capacity
b. Inspiratory capacity
c. Residual volume
d. Total lung capacity
e. None of the above
11. Which of these statements is correct?
a. Regular bronchioles are the most distal part of the respiratory tract to contain glands.
b. Larynx do contain significant amounts of smooth muscle
c. Goblet cells are abundant in the small bronchi and respiratory bronchioles
2
WITH CORRECT ANSWERS
, lOMoARcPSD|52690394
MCQs RESPIRATORY PHYSIOLOGY
RESPIRATORY PHYSIOLOGY
1. The partial pressure of oxygen in dry air inhaled by divers at a depth of 100 feet (4 atm) below
sea level is approximately
a. 160mmHg
b. 320mmHg
c. 640mmHg
d. 1280mmHg
e. none of the above
2. Two healthy women with identical tidal volumes are subjected to spirometry and blood gas
measurements. Subject A doubles her tidal volume and decreases her respiratory rate to ½
of baseline. Subject B decreases her tidal volume to ½ of baseline and doubles her
respiratory rate. Which of the following statements about the resulting alveolar ventilation
in the two women is true?
a. Alveolar ventilation is unchanged in both subjects
b. Alveolar ventilation increases in both subjects
c. Alveolar ventilation decreases in both subjects
d. Alveolar ventilation increases in subject A and decreases in subject B
e. Alveolar ventilation decreases in subject A and increases in subject B
3. Increased baroreceptor discharge acts via the medulla to
a. heart rate
b. stroke volume
c. vessel diameter
d. BP
e. renin secretion
4. A man breathing room air at sea level has an alveolar ventilation of 2L/min. The blood gases
show a PaCO2 of 48mmHg and a PaO2 of 70mmHg. The alveolar oxygen tension (PaO2 ) is
a. 150mmHg
b. 110mmHg
c. 100mmHg
d. 90mmHg
e. 60mmHg
5. Reduction of functional Hb associated with anaemia, met Hb, or CO poisoning does not produce
hyperpnoea because the
a. Blood flow to the carotid body is
b. Total arterial O2 content is maintained within normal range
c. Carotid body chemoreceptors are stimulated
d. Central chemoreceptors are stimulated
1
, lOMoARcPSD|52690394
MCQs RESPIRATORY PHYSIOLOGY
e. pO2 of arterial blood is normal
6. During a normal inspiration, more air goes to the alveoli at the base of the lung than to the
alveoli at the apex of the lung because
a. The alveoli at the base of the lung have more surfactant
b. The alveoli at the base of the lung are more compliant
c. The alveoli at the base of the lung have higher V/Q ratios
d. There is a more negative intra pleural pressure at the base of the lung
e. There is more blood flow to the base of the lung
7. The activity of the central chemoreceptors is stimulated by
a. An increase in the pCO2 of blood flowing through the brain
b. A decrease in the pO2 of blood flowing through the brain
c. A decrease in the oxygen content of blood flowing through the brain
d. A decrease in the metabolic rate of the surrounding brain tissue
e. An increase in the pH of the CSF
8. Metabolic functions of the lung include all of the following EXCEPT
a. Inactivation of bradykinin
b. Inactivation of prostaglandins
c. Inactivation of angiotensin II
d. Synthesis of prostaglandins
e. Synthesis of surfactant
9. Regarding V/Q differences in the lung
a. In healthy individuals, anatomic dead space is less than physiologic dead space
b. The relative change in blood flow from apex to base is less than relative change in ventilation
c. Ventilation/perfusion differences are due to gravity
d. Ventilation/perfusion ratio is low at the base
e. All of the above
10. A spirometer can be used to measure directly
a. Functional residual capacity
b. Inspiratory capacity
c. Residual volume
d. Total lung capacity
e. None of the above
11. Which of these statements is correct?
a. Regular bronchioles are the most distal part of the respiratory tract to contain glands.
b. Larynx do contain significant amounts of smooth muscle
c. Goblet cells are abundant in the small bronchi and respiratory bronchioles
2
