Question
Biology Question on excretory system
This is not a nitrogenous waste.
A
Creatinine
B
Purine
C
Allantoin
D
Citrulline
Answer
Citrulline
Explanation
Solution
Nitrogenous waste is any metabolic waste product that contains nitrogen. Creatinine is present in urine. Allantoin is the major nitrogenous waste in many insects. A few animals excrete nitrogen that comes from the metabolism of purines (eg, adenine and guanine). Among all the given options, citrulline is not a nitrogenous waste.