Amphibians use their lungs for respiration, but they also absorb oxygen through their skin. They breath underwater by absorbing dissolved oxygen in the air or gills.
No, all modern amphibians do not only use their lungs for respiration. They can also respire through their skin and tissues in the lining of their mouth.
Amphibians can live in water or land environments, as long as the land environment is moist enough for them, while fish can only live in the water. Their gills are specifically designed to filter oxygen from the water.
Pulmonary respiration takes place only in the lungs. It is a process in which oxygen is taken in and carbon dioxide is expelled from the body. During pulmonary respiration, the exchange of gases occurs between the alveoli in the lungs and the capillaries surrounding them.
Mammals have lungs, as do amphibians, reptiles, and birds. Fish are the only chordates that have gills rather than lungs.
In human lungs. Because lungs is the only part where cellular respiration takes. This is the only part that helps in take in oxygen, utilize it to other parts and then give off Carbon Dioxide.
There are many different varieties of salamanders. Most of these salamanders have both gills, and lungs. There are also some that have gills, but then lose them as they get older. They then use lungs for breathing.
The lungs of a pig is larger and more evolved than that of a frog. This is because the frog has other organs of respiration apart from the lungs e.g the skin (cutaneous respiration) and mouth(buccal respiration) hence does not depend on the lungs solely for respiration unlike the pig which has thev lung as its only respiratory organ
Lungs, just like us. However, some amphibians do not have lungs, and all amphibians breathe through their skin (as the only method or on the side if they have lungs). Axolotls and the like, that stay in water for their entire life, breathe through gills behind the head, and their skin (but that really doesn't count as you asked for adults and the axolotl is an eternal larva :P).
One of the similarities of lungs and gills is that both are used for breathing in and out. Only that gills are found in fishes and young amphibians and lungs are found in birds, mammals, reptiles and adult amphibians.
As young amphibians have external gills. As adults their skins are permeable to gas exchange. Reptiles breath only with their lungs.
Since frogs spend most of their lives in water there is a huge advantage to having a redundant system of getting oxygen. The need for a frog to be able to breathe without surfacing during the winter months makes "skin breathing" very advantageous. The use of lungs is effective when the frog is on the surface (especially when completely out of the water).
Neither. It is a fish. That is why it is called a “Puffer fish.”