Question

State the differences between artery, vein and capillary.

Answer 1

Differences between artery, vein, and capillary:

Arteries	Veins	Capillaries
Arteries are tough, thick, and elastic tubes.	Veins are thin-walled and non-elastic tubes.	Capillaries are very thin-walled tubes.
They have a narrow lumen.	They have a wide lumen.	They have a very narrow lumen, just wide enough for a red blood cell to pass through it.
They carry blood away from the heart to the various organs of the body, at high pressure.	They transport blood towards the heart from various organs, at low pressure.	They carry blood from the arteries to the veins.
They do not have valves.	They have valves to prevent the backward flow of the blood.	They do not have valves.
They transport only oxygenated blood (except for the pulmonary artery).	They transport only deoxygenated blood (except for the pulmonary vein).	They exchange oxygen, carbon dioxide, water, and salts between the blood and the surrounding tissues