What is the metarteriole?

Answer 1

A Metarteriole (or arterial capillary or precapillary sphincter) is a short vessel(s) that link arterioles and capillaries. Instead of a continuous tunica media, they have individual muscle cells placed a short distance apart, each forming a precappilary sphincter that encircles the entrance to one capillary. Constriction of these sphincters reduces or shuts off blood flow through their respective capillaries and diverts blood to tissues or organs elsewhere.