What are blood vessels?

Blood vessels are the channels or vessels in the human or animal body through which blood circulates across the body.

Arteries, veins and capillaries are the blood vessel present in the body.

The vessels that carry blood away from the heart are called arteries, and they further divide into very small branches which are arterioles. Very small branches that collect the blood from the various organs and parts are called venules, and they unite further to form veins, which return the blood to the heart.

Capillaries are minute thin-walled vessels that connect the arterioles and venules; it is through the surface of the capillaries that nutrients and wastes are exchanged between the blood and body tissues.