Question

1. Increased ventilation during exercise is primary caused by

1. Changes in the pO2
2. Changes in the pCO2
3. Neurogenic stimulus from the cortex
4. All of the above

2. Functional Residual Capacity is?

            a. Extra volume of air that can be expelled during a maximal exhalation

            b. The volume of air left in the lungs after normal breath

            c. The minimum volume of air remaining in the lungs even after a maximal expiration

            d. The volume of air in the lungs at the end of a normal passive expiration

3. Central Chemoreceptors are sensitive to changes in

            a. pCO2

            b. pO2

            c. Concentration of H+

            d. None of the above

4. What kind of breathing will result in normal pulmonary ventilation but no alveolar ventilation?

            a. Normal breathing

            b. Rapid shallow breaths (hyperventilation)

            c. Slow deep breaths

            d. Breathing during exercise

Answer 1

1.ANSWER: a. Changes in pO2

Reason: During exercise the demand for oxygen increases hence changes in pO2 causes increased ventilation.

2. ANSWER: B. The volume of air present in the lungs after normal breath.

Reason: Functional residual capacity is the volume of air present in the lungs even after passive expiration.

3.ANSWER: A. pCo2.

Reason: The central chemoreceptors are more sensitive to the changes in pCo2 in arterial blood and ph in the CSF.

4. ANSWER: b. Rapid shallow breaths (hyperventilation).

Reason: During hyperventilation patient experiences only pulmonary breathing but no alveolar breathing will be present.