arterial tree

anatomy

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June 17, 2026

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The arterial tree is a network of vessels that carry oxygenated blood from the heart to the body's tissues. The main artery is the aorta, which branches into smaller arteries and then into arterioles. These arterioles lead to capillaries, where oxygen and nutrients are delivered, and waste products are collected.1

Arteries have strong, elastic walls with three layers: the tunica intima, tunica media (muscle and elastic fibers), and tunica adventitia (connective tissue). This structure allows them to withstand the high pressure from the heart's pumping action, creating a pulse. Blood flow is regulated by the widening or narrowing of arterioles, directing blood to where it's most needed. The exception is the pulmonary artery, which carries deoxygenated blood to the lungs.213

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human cardiovascular system
The arterial tree—the branching system of arteries—terminates in short, narrow, muscular vessels called arterioles, from which blood enters simple endothelial tubes (i.e., tubes formed of endothelial, or lining, cells) known as capillaries. These thin, microscopic capillaries are permeable to vital cellular nutrients and waste products that…
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The arterial tree—the branching system of arteries—terminates in short, narrow, muscular vessels called arterioles, from which blood enters simple endothelial tubes (i.e., tubes formed of endothelial, or lining, cells) known as capillaries. These thin, microscopic capillaries are permeable to vital cellular nutrients and waste products that…
Read More