Question

Which of the following is the first step of glycolysis?

• A. Breakdown of glucose
• B. Phosphorylation of glucose
• C. Conversion of glucose into fructose
• D. Dehydrogenation of glucose

Answer 1

The correct option is B Phosphorylation of glucose

Glycolysis is a process in which one mole of glucose is partially oxidized into two moles of pyruvate in a series of enzyme-catalyzed reactions.

The first step of glycolysis is phosphorylation of Glucose in which Glucose is phosphorylated by ATP to form a glucose 6-phosphate. The negative charge of the phosphate prevents the passage of the glucose 6-phosphate through the plasma membrane, trapping glucose inside the cell. This irreversible reaction is catalyzed by the enzyme "hexokinase".

So, the correct answer is B.