AP BIOLOGY

Detailed explanation-1: -Diffusion is the process by which exchange of gases take place between blood and body tissues. Respiratory gas is transported to each and every cell by blood. Tiny capillaries provide the blood flow to even remote parts of the body tissue.

Detailed explanation-2: -Capillaries are the simplest blood vessels. They are the smallest of the body’s blood vessels. The major function of capillaries is the exchange of gases and nutrients between blood and tissues.

Detailed explanation-3: -Exchange of material such as oxygen, nutrients and other waste between blood and tissue occur in capillaries. So the primary function of capillaries is to exchange the material to other body parts. In lungs, capillaries absorb oxygen and release carbon dioxide.

Detailed explanation-4: -Capillaries allow exchange of substances with body tissues through their thin walls. As blood travels at high pressure in the arteries towards the capillaries, pressure filtration occurs which results in plasma passing through the capillary wall into the tissue fluid which surrounds the cell.