<P> The nitrogen compounds through which excess nitrogen is eliminated from organisms are called nitrogenous wastes ( / naɪˈtrɒdʒɪnəs / ) or nitrogen wastes . They are ammonia , urea , uric acid , and creatinine . All of these substances are produced from protein metabolism . In many animals , the urine is the main route of excretion for such wastes ; in some , the feces is . </P>
<P> The nitrogen compounds through which excess nitrogen is eliminated from organisms are called nitrogenous wastes ( / naɪˈtrɒdʒɪnəs / ) or nitrogen wastes . They are ammonia , urea , uric acid , and creatinine . All of these substances are produced from protein metabolism . In many animals , the urine is the main route of excretion for such wastes ; in some , the feces is . </P>
nitrogenous wastes may be produced as a result of the metabolism of
nitrogenous wastes may be produced as a result of the metabolism of
protein
protein