Question

(a) Draw a diagram of human respiratory system and label the following:

(i) part where air is filtered by fine hair and mucus

(ii) part which terminates in balloon – like structures

(iii) balloon – like structures where exchange of gases takes place.

(iv) part which separates chest cavity from abdominal cavity.

(b) Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms?

Answer 1

(a)

(b) Quantity of dissolved oxygen is fairly low in water as compared to the amount of oxygen in air. Aquatic organisms therefore have to breath faster than terrestrial organisms to absorb the required amount of oxygen from the water.