Metabolic waste
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Metabolic wastes or excrements are substances left over from metabolic processes which cannot be used by the organism, and must therefore be excreted. This includes nitrogen compounds, water, CO2, pho
Placental mammals expel urine from the bladder through the urethra during urination.
Urine
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Urine is the fluid excreted by the kidneys of vertebrates to clear the bloodstream of excess water and metabolic by-products including urea, uric acid, and creatinine.
Metabolic waste
…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, it is the feces. Ammonotelism is the excretion of ammonia and ammonium ions. Ammonia (NH3…
Sample of human urine
Tigers spray small quantities of urine to mark their territories.
Urine containing uric acid crystals under the microscope
Medical experts have long connected urine colour with certain medical conditions. A medieval chart showing the medical implications of different urine color