Describe the general structure of the arterial wall.

Tunica intima: luminal (innermost) layer consisting of a single thickness of endothelial cells
Internal elastic lamina: separates the tunica intima and the tunica media
Tunica media: thickest layer of the vessel wall, consisting of smooth muscle cells
External elastic lamina: separates the tunica media and the tunica externa
Tunica adventitia: outermost layer, connective tissue sheath