Final answer:
Urea and uric acid are products of the breakdown of proteins. Urea is the main waste product in mammals, while uric acid is the major waste product in birds, reptiles, and terrestrial arthropods.
Step-by-step explanation:
Urea and uric acid are products of the breakdown of proteins. Nitrogenous wastes, such as urea and uric acid, are produced during the catabolism of proteins in the body. Urea is the main waste product in mammals, while uric acid is the major waste product in birds, reptiles, and terrestrial arthropods.