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.
Q: This pathway's first enzyme, a transcarbomylase, requires an input of carbomyl phosphate. The synthetase at this pathway's antepenultimate step requires aspartate, which is dehydrated and combined with citrulline. Sometimes called the Krebs-Henseleit cycle, it requires three ATP, which it reduces to two ADP and an AMP. This double-celled cycle regenerates its required fumarate from arginosuccinate, after which arginase produces its namesake compound. FTP, name this biological pathway, the first metabolic pathway discovered, that degrades amino acids to a certain nitrogenous waste product.
A:
Science