Chapter 41: Regulation of Respiration

Chapter 41: Regulation of Respiration

Complete Chapter Questions With Answers

Sample Questions Are Posted Below

1. Five hours after an uneventful knee surgery, a conscious 50-year-old woman has minor heart pains and a decrease in systolic blood pressure from 110 to 90 mmHg. Arterial blood gas analysis on her breathing room air shows:

pH                         7.30

pCO₂                     52 mmHg

pO₂                        58 mmHg

Which of the following is the most likely cause of these findings?

1. Alveolar hypoventilation
2. Cardiac failure
3. Hypoxia due to anesthetic gases
4. Pulmonary hypertension

ANS: A

2. Voluntary apnea (breath-holding) for 60 seconds will:

1. Decrease alveolar pCO₂
2. Increase arterial pO₂
3. Inhibit the arterial chemoreceptors
4. Increase alveolar pCO₂

ANS: D

3. Which of the following play a part in the increase in ventilation with moderate exercise?
4. Reflexes from moving limbs
5. Decrease in body temperature
6. Fall in arterial pO₂
7. Rise in arterial pCO₂

ANS: A

4. A 9-year-old boy decided to find out how long he could breathe into and out of a paper bag. After ~2 minutes his friends noticed that he was breathing very rapidly and forced him to stop. Which of the following was the most potent stimulus for the boy’s hyperventilation?

1. Decreased arterial PO₂
2. Increased arterial PO₂
3. Increased arterial PCO₂
4. Decreased arterial PCO₂
5. Increased pH

ANS: C