Question

Why do amphibians breathe through skins and lungs?

Answer 1

Respiration is an oxidation process which involves the degradation of a complex organic compound, hence carbon dioxide and water and energy are produced.

Amphibians such as frogs use more than one organ of respiration during their life. They breathe through gills while they are tadpoles. Mature frogs breathe mainly with lungs and also exchange gas with the environment through the skin.

Their skin has to stay wet in order for them to absorb oxygen so they secrete mucous to keep their skin moist. Oxygen absorbed through their skin will enter blood vessels right at the skin surface that will circulate the oxygen to the rest of the body. There are a few amphibians that do not have lungs and only breathe through their skin.

Then later most develop into land animals with lungs for breathing air. Lungs can also help in the water. Filling the lungs with air gives a frog a better buoyancy, making it float more easily.