Question

oxygen diffuses into the capillaries of the lungs because there is a) a higher concentration of o2 in the alveoli than the capillaries. b) a higher concentration of o2 in the capillaries than the alveoli. c) a higher concentration of co2 in the alveoli than the capillaries. d) a higher concentration of co2 in the capillaries than the alveoli. e) an equal concentration of o2 in the alveoli and the capillaries.

Explanation:

Diffusion is the movement of a substance from an area of high concentration to an area of low concentration. Oxygen diffuses from the alveoli (where it is highly concentrated after inhalation) into the capillaries (where it is less concentrated) in the lungs.

Answer:

A. a higher concentration of O₂ in the alveoli than the capillaries.