Arteries are the blood vessels in the Cardiovascular System which carry oxygenated blood from the heart to the rest of the body, with the exception of the Pulmonary Artery, which carries deoxygenated blood from the heart to the lungs. There is around 160 major arteries in the human body, and the largest artery is called the Aorta. Artieries branch into arterioles.
Like all major blood vessels, arteries consist of a layer of endothelial cells, a layer of smooth muscle cells and a layer of collagen. However, arteries are distinguished from other blood vessels because their smooth muscle layer is comperatively thicker than in veins. This is so that the blood, which is pumped from the heart at higher pressure, won't loose the pressure as it reaches the capillaries and allowing for efficient material exchange in the tissues. The total wall thickness of artieries is around 1.0 mm and internal diameter of around 4.0 mm, with the exception of the Aorta, which has wall thickness of 2.0 mm and internal diameter of 25.0 mm.
- McGrawHill LANGE "Cardiovascular Physiology" 7th Edition D. E. Mohrman, L. J. Heller chapter 1 "Overview of the cardiovascular system