Question

Out of arteries, capillaries, or veins, which is under the most pressure?

Answer 1

Arteries

Explanation:

Arteries are under the most pressure at any moment as they are directly under the pumping action of the heart, which pumps blood into the aorta. In such case, the high pressure has not been dissipated and that the pressure in the arteries is very high.

In capillaries, the blood vessels branch out in a large number, which gives a large total cross-sectional area, and this dramatically lower the pressure of the blood. In veins, the pressure becomes even lower to prevent blood from reentering the capillaries due to the reverse pressure gradient. Hence, the blood pressure are higher in arteries, and the highest of all at the aorta.