An amino acid produced in the urea cycle by the splitting off of urea from arginine.
An amino acid that occurs as a metabolic intermediate in the synthesis of urea, but not involved in protein synthesis, so of no nutritional importance.
An amino acid produced by the liver.
Ornithine is a nonessential amino acid synthesized from arginine. It is not utilized for the production of proteins but is integral in the urea cycle for the catabolism of amino acids and elimination of nitrogen from the body.
An *amino acid produced in the liver as a by-product during the conversion of ammonia to urea.
An amino acid formed when arginase hydrolyzes arginine. It is not present in proteins.