Question

Question 3

The absorption of nutrients and exchange of respiratory gases between blood and tissues takes place in –

(a) veins

(b) arteries

(c) heart

(d) capillaries

Answer 1

The answer is (d).

Capillaries are the extremely thin blood vessels where the exchange of substances and absorption of nutrients take place. They are the only link between arterioles and venules. Being the smallest of the body's blood vessels, only oxygen and glucose pass through the capillary walls and enter the cells. Waste products such as carbon dioxide pass back from the cells into the blood through capillaries to be taken back to the veins via the venules.