PATHOLOGY

Detailed explanation-1: -Capillaries are the smallest blood vessels in the body. How small are they? About ten of them equal the thickness of one human hair, and most are so small that only one blood cell can pass through them at a time.

Detailed explanation-2: -Why Are Capillaries Very Small in Size? Capillaries need to be small in order to facilitate oxygen and carbon dioxide gas exchange in cells. 3 They also play a role in fluid and nutrient exchange, forming the connection between the body’s smallest arteries (arterioles) and smallest veins (venules).

Detailed explanation-3: -Venules are the smallest veins and receive blood from capillaries. They also play a role in the exchange of oxygen and nutrients for water products. There are post-capillary sphincters located between the capillaries and venules.

Detailed explanation-4: -Blood leaves the capillary and enters the small venules. These venules become progressively larger vessels called veins.