There are four enzymes that can catalyze the first step of glycolysis.They are hexokinases I,II and III and glucokinase (hexokinase IV).Hexokinases I,II and III have Km values near 0.1 mM.Glucokinase has a Km range of 2-5 mM.If after a heavy meal the blood glucose level rises to 8 mM which statement will be true?

Question

Quizplus · Accepted Answer

Hexokinases I, II, and III have low Km values (near 0.1 mM), indicating high affinity for glucose and will be saturated at much lower glucose concentrations than glucokinase, which has a higher Km (2-5 mM). At 8 mM glucose, hexokinases I, II, and III would be operating at or near their maximum rate due to substrate saturation, while glucokinase, with its higher Km, would not yet be saturated and could still increase its activity as glucose levels rise.

There Are Four Enzymes That Can Catalyze the First Step