AP BIOLOGY

Detailed explanation-1: -Complete answer: Capillaries are essential for the delivery of oxygen to the tissue and in the exchange of nutrients between blood and interstitial fluid surrounding the cells. This function is well supported by the anatomy of the vessels.

Detailed explanation-2: -Capillaries, the Smallest Blood Vessels, Are the Sites for the Exchange of Water and Solutes Between the Bloodstream and the Interstitial Fluid.

Detailed explanation-3: -During gas exchange oxygen moves from the lungs to the bloodstream. At the same time carbon dioxide passes from the blood to the lungs. This happens in the lungs between the alveoli and a network of tiny blood vessels called capillaries, which are located in the walls of the alveoli.

Detailed explanation-4: -Capillaries are the blood vessels that reach out to small cells and tissue, helping in the exchange of materials like oxygen, carbon dioxide, and waste. Capillaries are semipermeable so that material can be exchanged with surrounding cells.