<prompt> True about drug metabolism ?Glucuronidation is phase I reactionMost common enzyme involved is Cyp 3A45Reduction is most common reactionCytochrome p450 is involved phase-II reaction  <response>: Ans. isbi.e., Most common enzyme involved is Cyp 3A45Ref: Katzung Ilthe p. 55Cytochrome p450 enzymes are microsomal enzymes that are involved in phase I metabolism of many drugs.Most of the drugs are metabolized by Cyp 3A4 isoform.Cyp 3 A 45 carryout biotransformation of largest number nearly 5O of drugs. 