THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -In the body, nitrogenous wastes tend to generate poisonous ammonia, which must be expelled. Urea is excreted by mammals, while uric acid is excreted by birds, reptiles, and some terrestrial invertebrates.

Detailed explanation-2: -Uric acid is a nitrogenous waste that is released by uricotelic organisms such as birds, reptiles, and other terrestrial organisms. Mammals are ureotelic i.e they release a nitrogenous waste called urea in their urine.

Detailed explanation-3: -Reptile and bird embryos must store their nitrogenous wastes inside the egg, and to keep from poisoning themselves, they manufacture uric acid.

Detailed explanation-4: -Uric acid is excreted by the animals which conserve water, at least during parts of their life cycle, such as birds, terrestrial reptiles, insects and some snails. In this case ammonia is converted into uric acid because it is less toxic than ammonia but it is insoluble in water.