Artery vs Vein
Circulatory system comprises blood vessels and the heart. Arteries and the veins are the two basic types of blood vessels that deliver blood to and from the heart. They both look like tubes, but they are adopted structurally and functionally to perform their own task. This article points out the basic differences of arteries and veins with regard to their anatomy and physiology.
Arteries carry oxygenated blood away from the heart to the systemic circulation to provide oxygen and nutrients to the distant tissues and organs except pulmonary arteries. The largest artery leaving the heart is the aorta. As it progresses, it becomes smaller and divide into branches and then into arterioles and capillaries to form capillary beds where the substance exchanges taking place. Next, the blood flow into post capillary venules, small veins, and large veins and eventually to superior and inferior vena cava entering the heart.
Arteries are deep seated and resist high pressure by having a thick wall. Endothelial cells in the tunica interna are more elongated, and the elastic membrane is well developed. Tunica media, which is medially situated, is more muscular and has many elastic fibers. Tunica externa, which is the outermost layer of the arterial wall, is less well developed and less strong. The lumen of the arteries are narrow and do not have valves. The flow in the arteries is pulsatile; it is palpable and reflects the rhythmic pumping action of the heart.
After death arteries are found to become empty of blood.
It is a low pressure collecting system from the return of blood from the capillary networks to the heart. They carry deoxygenated blood to the heart to be pumped into the lungs, to get oxygenated. (Except pulmonary veins)
Blood flows passively in the veins down a pressure gradient. General three layer arrangement of the vessels is seen in the veins, but the elastic and muscular components are much less prominent features. Wall of the vein is thinner and less elastic comparing to the artery. In the tunica interna endothelial cells are less flat and the elastic membrane is less well developed. Tunica media is less muscular and has few elastic fibers. Unlike in arteries tunica externa of the veins are well developed and stronger. The lumen is wide and posses valves allowing unidirectional flow of blood. Veins are superficially seated comparing to the arteries. Venous pulsations are not palpable but visible.
Even after death the veins contain blood.
What is the difference between artery and vein?
• Arteries carry oxygenated blood away from the heart while veins carry deoxygenated blood towards the heart ( Except pulmonary vessels).
• The wall of the artery is thicker and more elastic comparing to the vein.
• Arteries are deep seated while the veins are more superficial.
• The lumen of the artery is narrow but in the vein the lumen is wide.
• Arteries don’t have valves but veins do have to prevent back flow.
• After death the arteries become empty, but the veins do not.