If the stomach is present, some gastric secretions are usually produced. The intestine is basically a simple tube and little if any electrolyte retrieval occurs. Much electrolyte balance occurs through the gills. Terrestrial types have a more enlarged hindgut compared to fish. This larger, more complex intestine is mostly associated with water and electrolyte conservation.
Amphibians also possess a cloaca, which is a common reservoir for digesta and urine.
Amphibians also have simple, but functional kidneys, but these are much less efficient compared to those of mammals. They have a more pronounced large intestine. In herbivorous types, the large intestine can act as a site for microbial digestion, as in hindgut fermenters. As with amphibians, reptiles possess a cloaca, which functions as described above. Reptiles also possess kidneys that are more efficient than those of reptiles, but still less efficient than in higher animals.