Structure of the Vascular System
The layers of the vascular system are all similar in veins and ateries. The difference of thickness of various layers constitute the functional differences in the two types of vessels.
Tunica Intima
A single-cell endothelial layer that provides friction free lining for blood flow.
Tunica Media
This is a smooth muscle middle layer that controls the diameter of the blood vessel.
Tunica Adventitia
This is the outer layer which consists of fibrous connective tissues. Nerve fibers present in this layer, causing constriction and dilation.