GENERAL HISTOLOGY

Detailed explanation-1: -Thus, endothelial cells line the entire vascular system, from the heart to the smallest capillary, and control the passage of materials-and the transit of white blood cells-into and out of the bloodstream.

Detailed explanation-2: -Capillaries connect arterioles to venules. They allow the exchange of nutrients and wastes between the blood and the tissue cells, together with the interstitital fluid. This exchange occurs by passive diffusion and by pinocytosis which means ‘cell drinking’.

Detailed explanation-3: -The exchange of oxygen, nutrients, and waste between your blood and tissues also happens in your capillaries. This happens through two processes: Passive diffusion. This is the movement of a substance from an area of higher concentration to an area of lower concentration.