Concerning Blood Vessel Walls

Question

Concerning blood vessel walls,
A) the tunica adventitia is composed of connective tissue.
B) the tunica intima is smooth muscle.
C) the tunica media is an endothelial layer.
D) the walls of arteries are thinner and contain less elastic tissue than veins.
E) capillaries have the thickest walls of all the blood vessels.

Accepted Answer

The tunica adventitia, also known as the outer layer of blood vessel walls, is composed of connective tissue.

Answer: D
 Arteries have thicker walls and contain more elastic tissue than veins, which often have thinner walls and more valves.

Answer: E 
 Capillaries have the thinnest walls of all the blood vessels, consisting of a single layer of endothelial cells. The tunica media is in between the tunica intima and tunica adventitia and is composed of smooth muscle and elastic fibers.