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Why is urea formed in the liver of mammals?

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Diagram showing how epinephrine binding to a beta-adrenergic receptor on a cell membrane activates a G-protein, which then stimulates adenylyl cyclase to convert ATP into cyclic AMP (cAMP), leading to physiological effects such as increased heart rate, blood vessel dilation, and glycogen breakdown. — Biochemistry In biochemistry, researchers study the chemical substances and processes that occur in living organisms and cells. In particular, various processes by which cells gain energy, such as epinephrine-stimulated cAMP synthesis, have been deduced through the study of biochemistry.

In mammals, urea is formed in the liver as a vital detoxification process. When proteins are broken down for energy, amino acids undergo deamination, a process that releases ammonia.1234

Because ammonia is highly toxic to the body, it must be converted into a safer, more manageable substance. The liver processes this ammonia through a series of enzyme-catalyzed reactions known as the urea cycle. By incorporating ammonia and carbon dioxide into urea, the liver creates a readily soluble and harmless nitrogenous waste product. Once formed, urea is transported to the kidneys and excreted in the urine.1423