Chapter 39 Physical Principles of Gas Exchange; Diffusion of Oxygen and Carbon Dioxide Through the Respiratory Membrane

Chapter 39  Physical Principles of Gas Exchange; Diffusion of Oxygen and Carbon Dioxide Through the Respiratory Membrane

Complete Chapter Questions And Answers
 

Sample Questions

1. A child has been eating M&Ms (plain) and inhaled one down his airway, blocking his left bronchiole. Which of the following will describe the changes that occur?
Left Lung Alveolar pCO2 Left Lung Alveolar pO2 Systemic Arterial pO2
A.
B.
C.
D.
E.

ANS: C

2. If alveolar pO2 is 300 mmHg and alveolar pCO2 is 40 mmHg, what is the piO2 (humidified inspired pO2)?
A. 250 mmHg
B. 300 mmHg
C. 350 mmHg
D. 400 mmHg
E. 760 mmHg

ANS: C

3. Match the following with the letter indicating the most appropriate ANS: pO2 = 116 mmHg, pCO2 = 27 mmHg.
A. Atmospheric air
B. Alveolar air
C. Blood in the left heart
D. Blood in the right heart
E. Expired air

ANS: E

4. Twin patients, X and Y, both have respirations of 12/min, tidal volumes of 500 mL, and dead space of 100 mL. Patient X decreases the respiratory rate by half, and doubles the tidal volume. Patient Y doubles the respiratory rate and cuts the tidal volume in half. After two minutes, what conditions would best describe their alveolar gases, as compared to normal.
Patient X Alveolar ventilation Patient Y Alveolar ventilation
Alveolar pO2 Alveolar pCO2 Alveolar pO2 Alveolar pCO2
A.
B.
C.
D.
E.

ANS: C

5. In an individual, the pO2 and pCO2 in different alveoli varies as follows:

pO2
pCO2
Alveolus A
100
40
Alveolus B
40
45
Alveolus C
150
0
Which of the following statements is true?
A. Alveolus B is indicative of a dead space ventilation
B. Alveolus C is indicative of pulmonary shunt
C. Breathing 100% O2 would increase PO2 in alveolus C
D. Hyperventilation would increase PO2 in alveolus B

ANS: C