<prompt> Catecholamines are synthesized from -TyrosineTryptophanGlycineGlutamate  <response>: Ans. is a i.e., Tyrosine Amino 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, SerotoninGlycineArginineMethionineCreatineGlycine, cysteineBile saltsGlycineHemeAspartic acid and glutaminePyrimidine basesGlycine, aspartic acid, glutaminePurine basesb-alanineCoenzyme-AArginineNitric oxideHistidine, Arginine, lysineKeratinMethionine, lysineCarnitineGABAGlutamateGlutamate, cysteine, glycineGlutathione 