Physiology MCQ Flashcards
1
Q
- Which of the following is NOT a function of the lungs?
A. Metabolism
B. Serves as a reservoir of blood for the left ventricle.
C. It is a filter to protect the systemic vasculature
D. Facilitates the exchange of O2 and CO2 between air and blood.
E. All of the above are true.
A
e
2
Q
- Which of the following is in the correct path of CO2 from the tissue to the atmosphere?
A. Reaction with H2O to make H2CO3, dissociation to H+ and HCO3-, H+ combines with imidazole side chain of hemoglobin, carried back to lungs as HHb+ and HCO3-, reverse reaction forms CO2.
B. O2 is metabolized to CO2, reaction with H2O to make H2CO3, H2CO3 combines with imidazole side chain of hemoglobin, H2CO3Hb+ is carried back to the lungs, reverse reaction forms CO2.
C. Reaction with H2O to make H2CO3, dissociation to H+ and HCO3-, HCO3- combines with imidazole side chain of hemoglobin, carried back to the lungs as HCO3-Hb+ and H+, reverse reaction forms CO2.
D. O2 is metabolized to CO2, reaction with H2O to make H2CO3, dissociation to H+ and HCO3-, carried back to lungs in this form, reverse reaction forms CO2.
A
a
3
Q
3. Which of the following is NOT an effector of respiration? A. Heart B. diaphragm C. intercostals D. Trapezius.
A
d
4
Q
4. Which of the following is the first branching of the bronchial tree that has gas exchanging capabilities? A. Terminal bronchioles. B. Respiratory bronchioles. C. Alveoli D. segmental bronchi E. alveolar ducts.
A
b
5
Q
5. Which of the following could NOT be part of an acinus? A. alveolar sacs B. Alveolar ducts C. Terminal bronchioles D. Respiratory bronchiole
A
c
6
Q
- If you increased the left atrial pressure from 5 mmHg to 15 mmHg, what effect would that have on pulmonary circulation?
A. It would force blood the opposite direction.
B. It would increase the speed at which blood moves through the pulmonary circulation.
C. No change.
D. Blood flow would almost or completely stop.
A
d
7
Q
7. Which of the following concerning average lung volumes and capacities of a person at rest is TRUE? A. TLC>VC>TV>FRC B. TLC>FRC>VC>TV C. TLC>VC>FRC>TV D. TLC>FRC>TV>VC
A
c
8
Q
- Which of the following is NOT a normal occurance with increasing age?
A. Vital capacity of the lung decreases.
B. Residual volume increases.
C. Functional residual capacity increases.
D. Inspiratory capacity decreases.
E. Expiratory reserve volume increases.
A
e
9
Q
9. Which of the following spirometry measurements has the greatest sensitivity for detecting early air flow obstruction? A. FVC B. FEV1 C. FFE D. FEF25-75
A
d
10
Q
- Which of the following does NOT happen during inspiration?
A. The ribs move upward.
B. The diaphragm lifts up.
C. The antero-posterior dimensions of the chest are increased.
D. The tranverse dimensions of the thorax are increased.
E. The scalene and sternocleidomastoid muscles can be recruited for inspiration.
A
b
11
Q
- During inspiration, how does alveolar pressure compare to atmospheric pressure?
A. Alveolar pressure is greater than atmospheric.
B. Alveolar pressure is less than atmospheric.
C. Alveolar pressure is the same as atmospheric.
D. Alveolar pressure is one of the few pressures where the reference pressure is not atmospheric.
A
b
12
Q
12. Which of the following represents the pressure difference that acts to distend the lungs? A. Alveolar pressure B. Airway opening pressure C. Transthoracic pressure D. Transpulmonary pressure E. Esophageal pressure.
A
d
13
Q
- If a patient had a progressive lung disease that required an ever increasing pressure to fill the same volume of lung, how would the lung’s compliance be affected?
A. It would increase it.
B. It would stay the same.
C. It would decrease it.
D. These variables do not affect lung compliance.
A
c
14
Q
- An asthma sufferer finds she has to breathe at twice her normal rate. How does that affect her dynamic compliance?
A. It stays the same.
B. It decreases.
C. It increases.
D. Static compliance, not dynamic, is the variable affected by asthma.
A
b
15
Q
- According to the Law of Laplace, air should flow from the smaller alveoli to the larger, collapsing them. In the lungs, several factors counter that tendency, and stabilize the alveolar structures. Which of the following is NOT one of them?
A. Surfactant lowers surface tension to a greater degree when it is on a smaller surface area, allowing the smaller alveoli to stay open.
B. Mechanical stability is given by surrounding alveoli.
C. Transpulmonary pressure is lower for smaller alveoli, allowing them to stabilize in comparison to the bigger ones.
D. Surface tension at the gas-liquid interface increases as alveolar surface area increases.
A
c
16
Q
- Which of the following is FALSE concerning the production and role of lung surfactant?
A. It is part of a lipoprotein called dipalmitoyl phosphatidyl-choline.
B. It is synthesized by alveolar type II cells.
C. As the alveolar surface area decreases during the compression curve, the surfactant decreases the surface tension at a constant rate.
D. When surfactant density is decreased during expansion, surface tension initially rises rapidly, then slows down until it reaches the starting point.
A
c
17
Q
- Which of the following is NOT true concerning respiratory distress syndrome in premature infants?
A. Their ability to synthesize DPPC is limited.
B. Higher pressures are required to ventilate the lungs.
C. Lung compliance is low.
D. Positive pressure respirators are often used to assist them in breathing.
E. Alveoli tend to overexpand and sometimes burst at the end of inspiration.
A
e
18
Q
- Which of the following is NOT true at FRC?
A. It is about 75% TLC.
B. The elastic recoil of the chest wall is outward.
C. The elastic recoil of the lung is inward.
D. The relaxation pressure of the lung and chest wall combined is at atmospheric pressure.
A
a
19
Q
- If the lung were punctured, which of the following would happen?
A. The lung would collapse on the side of the puncture.
B. Both the lung and the chest wall would collapse on the side of the puncture.
C. The relaxation pressure of the chest wall would increase until it surpassed the atmospheric.
D. The relaxation pressure of the chest wall would increase, but stop before it reached atmospheric pressure.
A
a
20
Q
- Which of the following is FALSE concerning the airflow in the lungs?
A. During inspiration and expiration, the flow in the trachea and larger bronchi is turbulent.
B. Towards the middle of the bronchial tree, the flow is turbulent at the branches and laminar in between.
C. Near the end of the bronchial tree, the flow is laminar.
D. The acini have very small radii which significantly increases the total air flow resistance of the bronchial tree.
A
d