EVERYDAY SCIENCE

Detailed explanation-1: -The tunica externa (New Latin “outer coat"), also known as the tunica adventitia (New Latin “additional coat"), is the outermost tunica (layer) of a blood vessel, surrounding the tunica media. It is mainly composed of collagen and, in arteries, is supported by external elastic lamina .

Detailed explanation-2: -The outermost layer, which attaches the vessel to the surrounding tissue, is the tunica externa or tunica adventitia. This layer is connective tissue with varying amounts of elastic and collagenous fibers.

Detailed explanation-3: -Multiple venules join to form veins. The walls of venules consist of endothelium, a thin middle layer with a few muscle cells and elastic fibers, plus an outer layer of connective tissue fibers that constitute a very thin tunica externa.

Detailed explanation-4: -Abstract. Tunica adventitia or tunica externa is the outer layer of the blood vessel wall. It consists of connective tissue with vasa and nervi vasorum and plays a key role in vascular health.

Detailed explanation-5: -Aside from capillaries, blood vessels are all made of three layers: The adventitia or outer layer which provides structural support and shape to the vessel. The tunica media or a middle layer composed of elastic and muscular tissue which regulates the internal diameter of the vessel.