Which factor is key in allowing the body to absorb oxygen and expel carbon dioxide?
A) Variations in the pressures of the gases
B) Variations in the volume of the gases
C) Variations in vital capacity
D) Variations in tidal volume

Question

Quizplus · Accepted Answer

The exchange of gases in the lungs occurs because of the difference in pressure between oxygen and carbon dioxide. Oxygen diffuses from the alveolar space in the lungs into the blood because the partial pressure of oxygen in the alveoli is higher than the partial pressure of oxygen in the blood. Conversely, carbon dioxide diffuses from the blood into the alveoli because the partial pressure of carbon dioxide in the blood is higher than the partial pressure of carbon dioxide in the alveoli. Variations in pressure are therefore key in allowing the body to absorb oxygen and expel carbon dioxide.

Which Factor Is Key in Allowing the Body to Absorb