Artery

A blood vessel that carries blood away from the heart. Systemic arteries carry blood pumped from the left ventricle of the heart to all parts of the body except the lungs. The largest systemic artery is the aorta, which emerges from the left ventricle; other major systemic arteries branch off from the aorta. The pulmonary arteries carry blood from the right ventricle to the lungs. Arteries are tubes with thick, elastic, muscular walls able to withstand the high pressure of blood flow. The structure of arteries helps to even out the peaks and troughs of blood pressure caused by the heartbeat, so that the blood is kept flowing at a relatively constant pressure. (See also arteries, disorders of.)