Question

Name the site of exchange of material between the blood and the surrounding cells.

Answer 1

The exchange of material between blood and surrounding cells occur in capillaries. Capillaries are the tiny blood vessels responsible for connecting arteries and veins. Fluid movement between capillary and surrounding tissue is regulated by hydrostatic pressure and osmotic pressure.

Complete step by step answer: Capillaries are small, microscopic blood vessels (5-10 micrometres in diameter) that connect arteries and veins. Blood vessels of the arterial system carry blood away from the heart and blood vessels associated with the venous system carry blood back to heart. This is the main reason why tissues such as lungs, liver and kidney are found to be more active because they have an abundance of capillaries. Walls of capillaries are made up of a thin layer cell called endothelium surrounded by basement membrane. 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. In other parts, capillaries absorb carbon dioxide from the tissues and transfer the deoxygenated blood into veins. And also carry oxygenated blood from arteries and then transfer it to other parts of the body.

Additional Information:
White blood cells can use capillaries to overcome the site of infection. The transfer or exchange of material in capillaries occurs through two processes-
-Passive diffusion: Movement of material from area of high concentration to area of lower concentration.
-Pinocytosis: it is a process by which body cells actively take in small molecules like fats and proteins.

Note: The site of exchange of material between blood and other tissues is the capillary. It is a site responsible for utilization of oxygen by tissue and transporting carbon dioxide by lungs. Blood in capillaries can also be used to perform different blood testing.