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
Insulin acts on which enzyme during glycolysis? 
Select and explain. 
A. Glucokinase, B. Hexokinase, C. Glucose-6-phosphatase, D. Adenylate kinase
A: Glucokinase
Answer: A: Glucokinase 
Explanation: In glycolysis, insulin acts on hexokinase IV (i e. glucokinase) and hexokinase II, but not on other (I & III) hexokinase.