GROSS ANATOMY

Detailed explanation-1: -An arteriole (är-’tir-ē-, ōl) is a very small blood vessel that branches off from your artery and carries blood away from your heart to your tissues and organs. Arterioles are small arteries that link up to capillaries, which are smaller yet.

Detailed explanation-2: -The arterioles are the smallest arteries, with a caliber of between 0.3 mm and 10 microns (µm). The largest arterioles are endowed with three tunica, but the smallest arterioles, which lead into capillary beds, constitutes no more than a single layer of smooth muscle cells, arranged in a spiral around endothelium.

Detailed explanation-3: -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. Explain that smoking harms your blood cells and blood vessels, including tiny capillaries.