Which layers compose the arteries?

The correct answer is that arteries are composed of the layers known as the tunica intima, tunica media, and tunica adventitia.

The tunica intima is the innermost layer, consisting of a smooth endothelial lining that minimizes friction as blood flows through the lumen. The next layer, the tunica media, is made up of smooth muscle and elastic fibers, allowing the artery to control its diameter and manage blood pressure and flow through vasoconstriction and vasodilation. Finally, the tunica adventitia, or tunica externa, is the outer layer that provides structural support and elasticity to the artery, anchoring it to nearby tissues. This tri-layer structure is crucial for the arteries' function of withstanding and regulating high-pressure blood flow from the heart.

In this context, the distinction of the tunica adventitia as opposed to tunica external or other names highlights the terminology used in anatomy, further solidifying the understanding of vessel structure and function.