<prompt> Urea cycle occurs in which of the following body organs?LiverGastrointestinal tractSpleenKidney  <response>: The urea cycle also known as the ornithine cycle is a cycle of biochemical reactions occurring in many animals that produces urea from ammonia NH3. This cycle was the first metabolic cycle discovered Hans Krebs and Ku Henseleit, 1932, five years before the discovery of the TCA cycle. In mammals, the urea cycle takes place primarily in the liver, and to a lesser extent in the kidney. Ref: Textbook of Biochemistry By DM Vasudevan, 3rd Edition, Page163 