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What are the three layers of an artery wall?
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human cardiovascular system
The human heart is both a pump and a muscle. Its four chambers move blood efficiently, while cardiac muscle cells joined by intercalated disks synchronize each contraction.
The wall of an artery consists of three distinct layers, or coats:
- Tunica intima: The innermost layer, which consists of a lining of smooth endothelium and a network of connective tissue with elastic fibers.12
- Tunica media: The middle coat, which is typically the thickest layer in arteries. It is composed of smooth muscle cells and elastic fibers arranged in spiral layers, allowing the vessel to expand and recoil with the pulse.12
- Tunica adventitia: The outermost layer, which acts as a supportive and protective element. It is composed primarily of collagen and elastic fibers, providing a barrier that prevents the vessel from overexpanding.12