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
Conversion of glucose to glucose-6 phosphate in human liver is by 
Select and explain. 
A. Hexokinase only, B. Glucokinase only, C. Hexokinase and glucokinase, D. Glucose-6-phosphate dehydrogenase
C: Hexokinase and glucokinase
Answer: C: Hexokinase and glucokinase 
Explanation: Hexokinase and glucokinase may be considered as iso-enzymes. Glucokinase is under the influence of insulin; but hexokinase is not. Hexokinase is present in most tissues. Glucokinase with a high Km for glucose is present in liver and beta cells. Glucokinase is induced by insulin.
Reference: Vasudevan 7th  ed, pg 109