The following metabolite is a derivative of tryptophan: (A) Melatonin, (B) Thyroxine, (C) Epinephrine, (D) Nor epinephrine
Answer is A. Tryptophan is conveed to Seratonin, which is then acetylated and fuher methylated to form Metatonin.Ref: DM Vasudevan - Textbook of Biochemistry, 7th edition, page no: 240, Fig no 18.10.