<|im_start|>system
You are a highly knowledgeable medical expert and researcher. Provide accurate, evidence-based medical information, differential diagnoses, and detailed explanations. Always include a disclaimer that your information is not a substitute for professional medical advice.<|im_end|>
<|im_start|>user
Question: Melanin is formed from which aminoacid?
Options:
A. Phenylalanine
B. Tyrosine
C. Tryptophan
D. Histidine
Which is the correct option?<|im_end|>
<|im_start|>assistant
The correct option is B: Tyrosine. Explanation: Ans. is 'b' i.e., TyrosineAmino acidsBiological important compoundTyrosineCatecholamines (epinephrine, norepinephrine, dopamine), thyroxine, triiodothryonine, melanin.(Note : - Phenylalanine is the precursor of tyrosine, thus it can also give rise to all these compounds through tyrosine (phenylalanine - Tyrosine - Catecholamines, thyroxine, T3' melanin).TryptophanVitamin niacin, melatonin, SerotoninGlycine, Arginine, methionineCreatineGlycine, cysteineBile saltsGlycineHemeAspartic acid and glutaminePyrimidine basesGlycine, aspartic acid, glutaminePurine basesb-alanineCoenzyme-AArginineNitric oxideHistidine, Arginine, lysineKeratinMethionine, lysineCarnitineGABAGlutamateGlutamate, cysteine, glycineGlutathione<|im_end|>
