'Lock and Key model' of enzyme action was proposed by: (A) Emil Fisher, (B) Daniel Koshland, (C) Lenor Michaelis, (D) Maud Menten
Answer is A. Lock and key hypothesis By emil Fischer Active site is rigid Substrate has complimentary shape Demerits: 1. Rigid active site in reversible reaction. 2. Stabilization of transition state Ref: G n G 13th ed.