Question

Inosinic pathway occurs in
(A) Ammonotelic
(B) Uricotelism
(C) Ureotelism
(D) Genteelism.

Answer 1

Hint: The pathway that involves the synthesis of inosinic acid is called inosinic pathway. The first nucleotide formed during the synthesis of purine is known as inosinic acid. It is formed when adenosine monophosphate gets deaminated ( removal of amine group) and then hydrolysed water is added to form this acid .

Complete answer:
> Ammonotelism:- Ammonotelism is the process of excretion of ammonia and ammonium ions. Such animals are called ammonotelic. Such organisms do not form inosine. So inosinic pathways do not occur. Hence this option is incorrect.
> Uricotelism:- Uricotelism is the process of elimination of nitrogenous wastes from the body in the form of uric acid. The organisms which leads to the removal of uric acid from them are called uricotelic organisms. It also involves formation of inosine. So this option is true.
> Ureotelism:- The elimination of urea from an organism is termed as Ureotelism, and the animals that excrete their wastes majorly in various forms of nitrogen such as urea are called Ureotelic animals. This does not lead to formation of inosine. So this option is not correct
> Genteelism:- Guanotelism is the process of excretion seen in spiders and Scorpio.
Inosine is not formed in this so this option is incorrect.

Correct option is b that is uricotelism due to formation of inosine in this.


Note: Inosinic pathway is the most important step in metabolism. When uric acid is formed from ammonia in the liver it is known as an inosinic pathway. Uric acid is formed as the end result of breakdown of purines. When degradation of purine occurs it leads to the formation of inosinic acid. Inosinic acid is also released due to the deamination of adenine as it is also a purine. Guanylic acid is also released during the breakdown of purines.