arterys

Arteries are blood vessels that carry blood away from the heart, forming the main conduits of the circulatory system. In the systemic circulation they typically carry oxygen-rich blood, while pulmonary arteries carry oxygen-poor blood from the heart to the lungs.

Arteries have thick walls designed to withstand high blood pressure. They consist of three tunics: the innermost tunica intima (endothelium), the tunica media (smooth muscle and elastic fibers), and the tunica adventitia (outer connective tissue). Elastic arteries near the heart contain many elastic fibers to absorb pressure, while muscular arteries further away have more smooth muscle for distribution and regulation of flow.

The tree of arteries begins with large elastic arteries, which branch into muscular arteries and then into arterioles that feed capillary beds. Arterioles play a key role in controlling resistance and blood pressure through vasoconstriction and vasodilation.

Endothelial cells lining arteries release signaling molecules such as nitric oxide that regulate vascular tone and blood flow. Arterial health is influenced by cholesterol levels, blood pressure, and inflammatory processes.

Common conditions involve arteries: atherosclerosis with plaque buildup, hypertension affecting arterial walls, and aneurysms due to weakening of arterial walls. Terminology note: "arterys" is not standard; the correct plural is "arteries."