1. Respiration through skin is called cutaneous respiration.
2. In frog, skin is an additional or secondary or accessory respiratory organ.
3. Skin is a very important respiratory organ in both on land and water.
4. One-third of the total oxygen taken up by frog is through the skin.
5. Frog also keeps its skin moist. Frog skin has a large number of mucous glands which secrete mucous onto the surface of the skin.
6. The mucous layer retains water and reduces evaporation of water from body.
7. To keep the skin wet and moist frogs jump into water very frequently.
8. Frog skin is supplied with a large number of blood vessels which help in absorbing oxygen from the water.
9. The carbon dioxide produced during to respiration, diffuses out into the water through the blood vessels present in the skin of the frog.
