Question

Ureotelic animals are those in which the main nitrogenous waste product is

• A. Amino acids
• B. Urea
• C. Uric acid
• D. Ammonia

Answer 1

The correct option is B Urea

Animals accumulate ammonia, urea, uric acid, carbon dioxide, water and ions like $N{a}^{+}$, $K^{+}$, $C{l}^{-}$, phosphate, sulphate, etc., either by metabolic activities or by other means like excess ingestion. These substances have to be removed totally or partially. Ammonia, urea and uric acid are the major forms of nitrogenous wastes excreted by the animals. Thus animals may be ammonotelic, ureotelic or uricotelic respectively depending on the major excretory substance. Ammonia is the most toxic form and requires large amount of water for its elimination, whereas uric acid, being the least toxic, can be removed with a minimum loss of water.