Vitamin synthesised from amino acid is: (A) Thiamine, (B) Ribolflavin, (C) Biotin, (D) Niacin
Answer is D. Vitamin synthesized from amino acid niacin.Niacin, or nicotinic acid, is a substituted pyridine derivative. The biologically active coenzyme forms are nicotinamide adenine dinucleotide (NAD+) and its phosphorylated derivative, nicotinamide adenine dinucleotide phosphate.Reference: Lippincott Textbook of Biochemistry, fifth edition, pg no. 379