Question

(a) Why do lungs always have residual volume of air?
(b) Name the respiratory pigment in human beings and state
s present.​

Answer 1

Answer:

a The lungs always contain a residual volume of air so that during breathing cycle there is sufficient time for oxygen to be absorbed and for the carbon dioxide to be released. Residual Volume is important because it prevents the lungs from collapsing.

b A respiratory pigment is a molecule, such as hemoglobin in humans and other vertebrates, that increases the oxygen-carrying capacity of the blood. The four most common invertebrate respiratory pigments are hemoglobin, hemocyanin, hemerythrin and chlorocruorin.