Question

Define ureotelism and ammonotelism.

Answer 1

The type of excretion in which ammonia is excreted is called ammonotelism and the animals having this mode are called ammonotelic organisms such as aquatic animals. Ammonia is excreted in the form of ammonium ions.

When the nitrogenous waste is excreted in the form of urea, then it is called ureotelism. In the liver of ureotelic organisms such as sharks, mammals and some amphibians, ammonia combines with carbon dioxide and ATP to form urea by ornithine cycle.