This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
Which of the following enzyme does not catalyzes irreversible step in glycolysis ? 
Select and explain. 
A. Hexokinase, B. Phosphoglycerate kinase, C. Pyruvate kinase, D. Phosphofructokinase
B: Phosphoglycerate kinase
Answer: B: Phosphoglycerate kinase 
Explanation: Ans. is 'b' i.e., Phosphoglycorate kinase Glycolysis is regulated at 3 steps which are irreversible. These reactions are catalyzed by following key enzymes :? 1) Hexokinase and glucokinase 2) Phosphofructokinase - I 3) Pyruvate kinase.