Question

List three differences between the artery and vein.

Answer 1

Hint: Artery and vein are the blood vessels required for the transportation of gases, nutrients, hormones, etc. to and from the organs.

Complete answer:
These blood vessels along with the heart and blood together form the 'Circulatory system'.The major differences between an artery and a vein are:

	Arteries	Veins
Structure	They are thick and possess three layers made up of muscles and elastin protein.Their lumen is narrow.	They are thin and possess three layers but lesser elastic fibers. Their lumen is wider.
Location	They are deep-seated into the skin.	They are situated superficially in the skin tissue.
Function	They carry oxygenated blood and nutrients to the organs.	They carry impure blood rich in carbon dioxide and byproducts.

Additional information:
The wall of the artery and vein is made up of –
1. Tunica Externa- It is made up of collagen and elastic fibers.
2. Tunica media- It is made up of smooth muscles and elastic fibers.
3. Tunica intima- It is also made up of collagen and elastic fibers.

Note:
1. The pulmonary artery carries deoxygenated blood from the heart to the lungs.
2. Pulmonary vein carries oxygenated blood from the lungs to the heart.
3. Umbilical veins carry nutrients and oxygenated blood to the fetus from the mother during gestation.
4. Arteries possess valves to obstruct the backward flow of blood but veins lack such valves.