Question
Biology Question on respiration in plants
Which one of the following is the first step of glycolysis ?
A
Breakdown of glucose
B
Conversion of glucose into fructose
C
Phosphorylation of glucose
D
Dehydrogenation of glucose
Answer
Phosphorylation of glucose
Explanation
Solution
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".