In the Alveoli

Question

In the alveoli
A)oxygen diffuses into the blood while carbon dioxide diffuses out of the blood.
B)oxygen diffuses out of the blood while carbon dioxide diffuses into the blood.
C)both oxygen and carbon dioxide diffuse out of the blood.
D)both oxygen and carbon dioxide diffuse into the blooD.
E)no exchange with the blood occurs.

Accepted Answer

The alveoli are specialized structures in the lungs that enable gas exchange. Oxygen diffuses from the alveoli's airspaces into the capillaries, where it binds to hemoglobin in red blood cells to be transported to body tissues. Simultaneously, carbon dioxide produced in the tissues diffuses into the blood, from which is transported to the lungs to be exhaled. Thus, in the alveoli, oxygen diffuses into the blood while carbon dioxide diffuses out of the blood.