AP BIOLOGY

Detailed explanation-1: -Nitrogenous waste which is less toxic, soluble in water and formed during the Ornithine cycle is urea. Urea is the excretory product of mammals which is soluble in water and less toxic. Ornithine cycle is also known as urea cycle in which urea is formed from ammonia by some chemical reactions.

Detailed explanation-2: -Urea cycle (ornithine cycle) is the series of biochemical reactions, that converts the highly toxic ammonia and carbon dioxide to the much less toxic urea during the excretion of metabolic nitrogen derived from the deamination of excess amino acids. The urea is ultimately excreted in solution as urine.

Detailed explanation-3: -Ornithine cycle occurs in the liver which is associated with the formation of urea for excretion. At first it involves the conversion of proteins to form ammonia. The ammonia is then converted to form urea. Urea is a nitrogenous waste that is present in the urine of ureotelic organisms.

Detailed explanation-4: -Compared to ammonia and urea, uric acid is least toxic and least soluble in water.