Question

Breathing carbon monoxide can decrease VO2 max by

a. binding to hemoglobin to displace oxygen.
b. reducing pulmonary ventilation.
c. decreasing the number of red blood cells.
d. decreasing the arterial PO2 to half its normal value.

Answer 1

Breathing carbon monoxide can decrease VO2 max by binding to hemoglobin to displace oxygen.

Step-by-step explanation:

When carbon monoxide is present, it binds to hemoglobin preferentially over oxygen, resulting in very little oxygen being transported through the body. This decreases VO2 max by reducing the amount of oxygen available for aerobic metabolism. As a result, the body's ability to utilize oxygen during exercise is compromised. Therefore, option a. binding to hemoglobin to displace oxygen, is the correct answer.