In glycolysis, the first committed step is catalyzed by: (A) 2,3 DPG, (B) Hexokinase, (C) Pyruvate kinase, (D) Phosphofructokinase
Answer is B. Glucose enters glycolysis by phosphorylation to glucose 6-phosphate, catalyzed by hexokinase, using ATP as the phosphate donor. Under physiological conditions, the phosphorylation of glucose to glucose-6-phosphate can be regarded as irreversible. Hexokinase is inhibited allosterically by its product, glucose-6-phosphate. Reference: Harper; 30th edition; Page no: 169