The amount of urea which is excreted out in the urine per day of an adult human is

Terrestrial organisms have evolved other mechanisms to excrete nitrogenous wastes. The animals must detoxify ammonia by converting it into a relatively nontoxic form such as urea or uric acid. Mammals, including humans, produce urea, whereas reptiles and many terrestrial invertebrates produce uric acid. Animals that secrete urea as the primary nitrogenous waste material are called ureotelic animals. An adult human excretes, on average, 1 to 1.5 litres of urine per day with 25-30 gm of urea.