Urea Cycle QuizVersion en ligne Test your knowledge on the urea cycle and the effects of Arginase Deficiency! par Colin Lee A C E O U Starts with A A toxic waste product formed during the breakdown of proteins and amino acids. Starts with C An intermediate compound formed during the urea cycle, which is essential for the synthesis of urea. Starts with E A protein that catalyzes biochemical reactions in the body, such as the conversion of arginine to ornithine in the urea cycle. Starts with O An amino acid that plays a crucial role in the urea cycle by carrying out the conversion of citrulline to arginine. Starts with U A nitrogenous waste product that is formed in the liver during the urea cycle and excreted by the kidneys.