Correct option is D
Explanation-
Catabolism of Purines:
Adenine is converted to hypoxanthine, and guanine is converted to xanthine. Xanthine oxidase enzyme converts:
Hypoxanthine → Xanthine
Xanthine → Uric acid
Uric acid is the final product of purine degradation in humans and many other primates.
Incorrect options -
Option A - Xyloric acid
No such standard biological compound in purine metabolism. May be a distractor or incorrect name.
Option B - Allantoin
It is the further breakdown product of uric acid in non-primate mammals (e.g., rats, dogs) due to the enzyme uricase. Humans lack uricase, so uric acid is the end product in humans.
Option C - Urea
Urea is the end product of nitrogen metabolism (amino acid breakdown), not purine catabolism. It is produced via the urea cycle in the liver.
So, the correct answer is option D - Uric acid .
