When frogs are tadpoles they breathe underwater through their internal gills and their skin. Later on in life they develop into land animals and develop lungs for breathing air. Frogs breathe with their mouths closed and the throat sack pulls air through the nose and into their lungs. Their throat movements pull air through the nostrils and back into the lungs, then they breathe out with their bodies contracting. Frogs nostrils are placed on top of their head so that they are able to breathe at the same time that they are in the water so that they can always be on guard.
Breathing is a gas exchange that takes oxygen from the surroundings and lets out carbon dioxide. The frog’s lungs are not only useful for breathing on land, but are also helpful when the frog is in the water. This is because filling the lungs with air gives these creatures better buoyancy and makes floating easier.
Frogs are also able to breathe through their skin, with tiny blood vessels known as capillaries that are located under the outer skin layers. The African Hairy Frog has small lungs and during the breeding season, the male frogs of this species are known to get hair on their back legs. This is because it needs a high amount of oxygen during this time.