Question

The first nitrogenous waste of vertebrates is
(A) Amino
(B) Urea
(C) Ammonia
(D) Ammonium

Answer 1

Hint:- The Nitrogenous wastes of vertebrates are toxic ammonia. Ammonia is nitrogenous wastes that are removed from body fluids by the action of the kidney, in terrestrial vertebrates. Ammonia is a nitrogenous waste that is produced as a by-product of protein metabolism. Toxic ammonia is converted into less toxic by the animals.

Complete step-by-step solution:-
A. For terrestrial vertebrates, nitrogenous wastes are removed from body fluids by the action of the
kidneys, the same organ involved in maintaining water balance. Ammonia is the direct waste produced
as a byproduct of protein metabolism. In animals, ATP is converted into ammonia to either form of
nitrogenous waste. Ammonia is produced naturally in soil by bacteria, decaying plants, and animals, and
animal wasted.
B. Amino (amino) group is a monomer of protein.
Urea is a water-soluble organic compound formed by the metabolism of proteins and excreted in the
urine. The major component of human urine is Urea.
C. Ammonium is an ammonium action.
D. The animals must expend cellular energy (ATP) to convert ammonia to either form of nitrogenous
waste.
So, the correct answer is Ammonia, option (C).

Additional information:-
- Nitrogen waste in birds and reptiles is Uric acid.
- Many adults, amphibians, and some marine species excrete urea.

Note:- Metabolic processes produce waste, and a great deal of this is in the form of nitrogen. This combines with water to produce toxic ammonia. Animals must safely excrete these toxins. This is the function of the excretory system. An animal that excretes ammonia as a nitrogenous waste is called Ammonotelic.