This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Carbohydrates, Subject name: Biochemistry
The enzymes involved in Phosphorylation of glucose to glucose 6- phosphate are: 
Select and explain. 
A. Hexokinase, B. Glucokinase, C. Phosphofructokinase, D. Both A. and B.
D: Both A. and B.
Answer: D: Both A. and B. 
Explanation: Ans. D. Both (a) and (b)This is the first regulatory enzyme of Glycolysis. Hexokinase is present in all the tissues whereas Glucokinase is present only in the liver and is regulated by Insulin. It has high km and low affinity for glucose.