Page "Amphibian" Paragraph 56

Amphibians possess a pancreas, liver and gall bladder.

The liver is usually large with two lobes.

Its size is determined by its function as a glycogen and fat storage unit, and may change with the seasons as these reserves are built or used up.

Adipose tissue is another important means of storing energy and this occurs in the abdomen, under the skin and, in some salamanders, in the tail.

In aquatic amphibians, the liver plays only a small role in processing nitrogen for excretion, and ammonia is diffused mainly through the skin.

The liver of terrestrial amphibians converts ammonia to urea, a less toxic, water-soluble nitrogenous compound, as a means of water conservation.

In some species, urea is further converted into uric acid.

Bile secretions from the liver collect in the gall bladder and flow into the small intestine.

Salamanders lack a valve separating the small intestine from the large intestine.

In the small intestine, enzymes digest carbohydrates, fats, and proteins.

Salt and water absorption occur in the large intestine, as well as mucous secretion to aid in the transport of faecal matter, which is passed out through the cloaca.