This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Amino Acid Metabolism, Subject name: Biochemistry
[{'content': 'Rate limiting enzyme in catecholamine synthesis- \nSelect and explain. \nA. Dopa decarboxylase, B. N-methyltransferase, C. Dopamine hydroxylase, D. Tyrosine hydroxylase', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., Tyrosine hydroxylase DopaTyrosine hydroxylase--------- Tyrosinase ..-------- DopaTyrosine|Dopa decarboxylase| | TyrosinaseDopamine Throxine (T4)Dopaquinone|b-oxidaseTriiodothyronine|(b-bydroxylase) NorepinephrineMelanin|N -methyl transferase (N-methylation)Epinephrineo Tyrosine hydroxylase is the rate limiting enzy me in the synthesis of catecholamines and it catalyzes the con version of ty rosine into dopa.o Immediate precursor of norepinephrine is dopmine.", 'role': 'assistant'}]