Artery Vs. Vein

The human body has a complex system of blood vessels that allow blood to travel throughout the body. Arteries and veins are two of the main components of this system. Both equally important, these two types of vessels are quite different.
  1. Artery Structure

    • Arteries have three layers: a smooth inner layer; a strong, muscular layer; and a thin outer layer. Connective fibers in artery walls allow for the elasticity needed for the artery to function. Arteries are usually larger than veins.

    Artery Function

    • Arteries, with the exception of the pulmonary artery, carry blood away from the heart. They bring blood that is rich in oxygen to the body.

    Vein Structure

    • Veins also have three layers: a thin outer layer, a middle layer and a smooth inner layer. Veins are less muscular than arteries and have less elasticity.

    Vein Function

    • Veins, with the exception of the pulmonary vein, carry blood that has been used by body tissues, back to the heart. Veins carry blood and waste products to the heart where these will be processed through the lungs and given oxygen again.

    Differences

    • Arteries are larger, more muscular and more elastic than veins. They carry blood that is under pressure from having been pumped out of the heart. Veins are under much less pressure, so they are not as strong.

    Phlebotomy

    • Standard phlebotomy uses veins rather than arteries. Veins in the arms, wrists and hands may be used for blood-drawing purposes. Arterial blood is sometimes drawn, but with specific orders from a physician, because many complications may arise.

Cardiovascular Disease - Related Articles