Question

The most important respiratory organ of frog is
A. Buccopharyngeal cavity
B. Lung
C. Gills
D. Skin

Answer 1

Hint: The frog respires by three organs- the skin, the lungs and on the lining of the mouth. A frog may also breathe much like a human, by taking air in through their nostrils and down into their lungs.

Complete answer:
In this question, we have asked about the most important respiratory organ of the frog. The frog can respirate by three organs: the skin, in the lungs and on the lining of the mouth. When it respires through skin it is called cutaneous respiration and when respirate through lining of mouth it is called buccal respiration.

> Option A is buccopharyngeal cavity. In this a frog respiration occurs by their mouth.

> Option B is lungs. Frogs only breathe through lungs when necessary as they do not have diaphragm, which regulates the pressure in the lungs.

> Option C is Gills. As we know, frogs do not have gills.

> Option D. Is skin. When a frog respires through their skin, it is called cutaneous respiration. Skin of frogs is very thin so that gases can easily diffuse through this membrane. When frogs are submerged under the water, the other two respiration stops and they respire through their skin. Also when a frog is in hibernation, it respires through the cutaneous respiration. So, the most important respiratory organ of a frog is skin.

Hence, The correct answer is option (D).

Note: A frog's skin is moist and thin with blood vessels and capillaries close to the surface. The moisture on the skin dissolved oxygen from the air and water surrounding the frog and transmits it into the blood.