Which process is responsible for creating MOST of an animal's nitrogenous waste?

Question

Quizplus · Accepted Answer

Protein breakdown during metabolism produces the majority of an animal's nitrogenous waste. When proteins are metabolized, the nitrogen in them is converted to ammonia or urea, which are excreted as waste products. While nitrogen can also be obtained from food, the amount consumed is generally lower than that produced during protein metabolism. Respiration does not produce nitrogenous waste, and toxins in the environment may contribute to nitrogenous waste production but are not the primary source.

Which Process Is Responsible for Creating MOST of an Animal's