Why does a frog die when the skin dries out?

The frog belongs to the class Amphibians. These are the first land animals. They breathe atmospheric air with their lungs. But, their lungs are large-meshed, therefore, they provide the body of amphibians with oxygen only by 50%. Amphibians receive oxygen that is lacking in the body through the skin. Cutaneous respiration is possible while the skin is moist. Thus, when the skin dries out, the frog dies from a lack of oxygen. This is why frogs live along the shores of water bodies: if the skin is not moist enough, they dive into the water.