By what mechanism does gas exchange across the lung occur?

Question

Quizplus · Accepted Answer

Gas exchange across the lung occurs through simple diffusion, which is the passive movement of molecules from an area of high concentration to an area of low concentration. Oxygen moves from the air in the alveoli (high concentration) to the blood in the capillaries (low concentration), and carbon dioxide moves from the blood in the capillaries (high concentration) to the air in the alveoli (low concentration).

By What Mechanism Does Gas Exchange Across the Lung Occur