Question

In frog, cutaneous respiration takes place

• A. Only in water, when pulmonary respiration does not take place
• B. Only in water, but along with pulmonary respiration
• C. Only on land
• D. Always

Answer 1

The correct option is D Always

In frogs the process of respiration takes place through three respiratory surfaces - skin, lungs and lining of the mouth. However, when submerged in water, the frog respires through its cutaneous membranes on the skin as it is quite permeable to water and contains a large network of blood vessels. The cutaneous membrane allows the respiratory gases to readily diffuse directly. Even when out of water, mucus glands present in the skin help in the cutaneous respiration.

Therefore, the correct answer is option D.