In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Sodium phenylburate is often used to treat suffers of disorders of this pathway. Defects in transporters found in this pathway can lead to HHH syndrome and Lysinuric Protein Intolerance. N-acetylglutamate is an allosteric activator of a key enzyme in this pathway. Aspartate and Citrullyl-AMP are used in one step of this reaction to form arginosuccinate. Like a connected pathway, fumarate is a byproduct of this reaction. In the mitochondria, citrulline is formed using a transcarbamoylase. Two amino acids that are part of this pathway are arginine and ornithine, and this cycle is sometimes named for the later. This cycle allows the body to deal with overconsumption of protein. For 10 points, name this cycle which generates a namesake compound allows the body to remove excess nitrogen.
Science