The outermost layer of an artery or vein is called the
A) tunica intima
B) tunica media
C) tunica adventitia
D) endothelium

Question

Quizplus · Accepted Answer

The outermost layer of an artery or vein is called the tunica adventitia or tunica externa. This layer is composed of connective tissue and contains nerves, lymphatic vessels, and smaller blood vessels that supply the larger vessel walls. The tunica intima is the innermost layer, composed of endothelial cells and a thin layer of connective tissue. The tunica media is the middle layer, composed of smooth muscle and elastic fibers. The endothelium is the layer of cells lining the inner surface of blood vessels.

The Outermost Layer of an Artery or Vein Is Called