What is the function of the frog's kidney?

The function of a frog’s kidney is to excrete excess water. While on land, frogs also use their kidneys to replace water lost through evaporation in the skin.

Frogs are amphibians that eat insects and small animals. There are about 4,740 different species of frogs found throughout the world, with 90 of those species are found in the United States. Frogs are found on every continent except Antarctica, but most are found in tropical climates. They live on land near swamps, ponds or in damp places. Frogs soak water in through their skin, and if their skin dries out they will die. They never close their eyes and can see forwards, sideways and upwards at the same time.