The enzyme which converts glucose to glucose 6-phosphate is

Options

A. Phosphorylase
B. Glucose-6 phosphatase
C. Hexokinase
D. Pyruvic acid to lactic acid.

Answer

To solve the question, "The enzyme which converts glucose to glucose 6-phosphate is," we will follow these steps:

### Step 1: Understand the process of glycolysis
Glycolysis is a metabolic pathway that converts glucose into pyruvic acid, producing ATP and NADPH in the process. The first step of glycolysis involves the phosphorylation of glucose.

### Step 2: Identify the phosphorylation of glucose
In the first step of glycolysis, glucose is phosphorylated to form glucose 6-phosphate. This reaction is crucial for trapping glucose inside the cell and preparing it for further breakdown.

### Step 3: Identify the enzyme responsible for this reaction
The enzyme that catalyzes the phosphorylation of glucose to glucose 6-phosphate is hexokinase. Hexokinase transfers a phosphate group from ATP to glucose, resulting in the formation of glucose 6-phosphate.

### Step 4: Eliminate incorrect options
- **Phosphorylase**: This enzyme is involved in the breakdown of glycogen, not the phosphorylation of glucose.
- **Glucose 6-phosphatase**: This enzyme removes a phosphate group from glucose 6-phosphate, converting it back to glucose.
- **Pyruvic acid to lactic acid**: This refers to a different metabolic pathway (lactic acid fermentation) and is not relevant to the conversion of glucose to glucose 6-phosphate.

### Conclusion
The correct answer is **hexokinase**.

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