Conversion of glucose to glucose-6 phosphate in human liver is by
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
Hexokinase only
Glucokinase only
Hexokinase and glucokinase
Glucose-6-phosphate dehydrogenase