Answer: Urea
When the body breaks down proteins (polymers of amino acids), whether because of famine or because there are too many amino acids in the body, the amino group containing nitrogen must be removed and discarded. This is discarded from a mammal's body in the form of urea.
Explanation:
In mammals such as humans, amino nitrogen is excreted as urea. Hence, mammals are referred to as ureotelic animals.
Unlike mammals, amino nitrogen is excreted as ammonia in aquatic animals while as uric acid in reptiles and birds.
