'''Uric acid''' is the main form of nitrogenous waste with lesser amounts of ammonia and urea depending on the species, the natural environment and degree of water conservation required. Uric acid is excreted by tubular secretion rather than urea by glomerular filtration. | '''Uric acid''' is the main form of nitrogenous waste with lesser amounts of ammonia and urea depending on the species, the natural environment and degree of water conservation required. Uric acid is excreted by tubular secretion rather than urea by glomerular filtration. |