During glycolysis, glucose is first changed to

Options

A. Glucose 6-phosphate
B. Fructose 6-phosphate
C. Glucose 1,6-phosphate
D. Adenophosphate bond.

Answer

**Step-by-Step Solution:**

1. **Understanding Glycolysis**: Glycolysis is the first step in the process of cellular respiration, which occurs in the cytoplasm of the cell. It is a series of reactions that break down glucose into smaller molecules.

2. **Initial Substrate**: The process begins with glucose, a six-carbon sugar molecule.

3. **First Conversion**: The first step in glycolysis involves the conversion of glucose into glucose-6-phosphate. This conversion is facilitated by an enzyme known as hexokinase.

4. **Phosphorylation**: The conversion of glucose to glucose-6-phosphate is a phosphorylation reaction, meaning that a phosphate group is added to the glucose molecule. This step requires the input of energy in the form of ATP, which is used to add the phosphate group.

5. **Conclusion**: Therefore, during glycolysis, glucose is first changed into glucose-6-phosphate.

**Final Answer**: Glucose is first changed into glucose-6-phosphate during glycolysis.

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