ATP does not provide phosphate in the reaction

Options

A. Glucose `rarr` Glucose 6-P
B. Fructose `rarr` Fructose 6-P
C. PGAL `rarr` 1:3-diPGA
D. PEPA `rarr` Pyruvic acid.

Answer

To solve the question "ATP does not provide phosphate in the reaction," we will analyze each option provided in the context of glycolysis, focusing on whether ATP contributes a phosphate group in the reaction.

### Step-by-Step Solution:

1. **Understanding the Role of ATP in Glycolysis**:
- ATP (adenosine triphosphate) is often involved in phosphorylation reactions where it donates a phosphate group, converting into ADP (adenosine diphosphate).

2. **Analyzing Each Option**:
- **Option A: Glucose to Glucose 6-Phosphate**:
- In this reaction, ATP donates a phosphate group to glucose, forming glucose 6-phosphate. This reaction is catalyzed by hexokinase. Thus, ATP provides a phosphate here.
- **Conclusion**: This option is incorrect.

- **Option B: Fructose to Fructose 6-Phosphate**:
- Similar to the first reaction, ATP donates a phosphate group to fructose to form fructose 6-phosphate, also catalyzed by hexokinase. Therefore, ATP is involved in this reaction as well.
- **Conclusion**: This option is incorrect.

- **Option C: 3-Phosphoglyceraldehyde to 1,3-Bisphosphoglyceraldehyde**:
- In this reaction, an inorganic phosphate (not from ATP) is added to 3-phosphoglyceraldehyde to form 1,3-bisphosphoglyceraldehyde. The enzyme glyceraldehyde 3-phosphate dehydrogenase catalyzes this reaction. Here, ATP does not provide a phosphate group.
- **Conclusion**: This option is correct.

- **Option D: Phosphoenolpyruvic Acid to Pyruvic Acid**:
- In this reaction, phosphoenolpyruvic acid donates a phosphate group to ADP to form ATP, but ATP is not providing a phosphate to the substrate. Thus, ATP is not involved in donating a phosphate in this reaction.
- **Conclusion**: This option is incorrect.

3. **Final Answer**:
- The correct option where ATP does not provide a phosphate group is **Option C: 3-Phosphoglyceraldehyde to 1,3-Bisphosphoglyceraldehyde**.