Which of the different kinds of nitrogenous wastes is most toxic?Multiple choice question.Uric acidUreaAllantoinAmmonia

The most toxic nitrogenous waste among the options provided is:

Ammonia

Explanation

1. Ammonia is a direct product of protein metabolism and is highly soluble in water. Its high toxicity requires rapid excretion, often seen in aquatic organisms that can afford to lose water easily.

2. Urea is less toxic than ammonia and is excreted by mammals. It requires less water for excretion than ammonia.

3. Uric acid is even less toxic and is excreted by organisms like birds and reptiles in a solid form, minimizing water loss.

4. Allantoin is a byproduct of uric acid metabolism and is generally non-toxic.

Thus, ammonia stands out as the most toxic nitrogenous waste product, as it requires a significant amount of water for excretion and can be harmful in higher concentrations.