This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'Which of the following is the rate limiting enzyme in glycogenesis? \nSelect and explain. \nA. Glucokinase, B. Glycogen phosphorylase, C. Glycogen synthase, D. Branching enzyme', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Glycogen synthase catalyzes the formation of a glycoside bond between C-1 of the glucose of UDPGlc and C-4 of a terminal glucose residue of glycogen, liberating uridine diphosphate (UDP).\nThe principal enzymes controlling glycogen metabolism glycogen phosphorylase and glycogen synthase—are regulated in opposite directions by allosteric mechanisms and\xa0 covalent modification by reversible phosphorylation and dephosphorylation of enzyme protein in response to hormone action.\n\nRate Limiting Steps\n\nGlycogenesis: Glycogen synthase.\nGlycogenolysis: Glycogen phosphorylase.\n\nHarper 30th edition Pg-179,175', 'role': 'assistant'}]