Which of these reactions is a multi step process ?

Options

A. Glucose `rarr` Glucose -6- phosphate
B. Fumarate `rarr` Oxaloacetate
C. PEPA `rarr` PA
D. Succinyl CoA `rarr` Succinate

Answer

To determine which of the given reactions is a multi-step process, let's analyze each option step by step.

### Step 1: Analyze the first reaction - Glucose to Glucose 6-Phosphate
- This reaction is the first step of glycolysis.
- It is catalyzed by the enzyme hexokinase.
- This reaction involves the phosphorylation of glucose to form glucose 6-phosphate.
- **Conclusion**: This is a single-step process.

**Hint**: Identify the enzymes involved and whether the reaction involves multiple transformations.

### Step 2: Analyze the second reaction - Fumarate to Oxaloacetate
- This reaction is part of the citric acid cycle (Krebs cycle).
- It involves two steps:
1. Fumarate is converted to malate.
2. Malate is then converted to oxaloacetate.
- The enzymes involved are fumarase for the first step and malate dehydrogenase for the second step.
- **Conclusion**: This is a multi-step process.

**Hint**: Look for reactions that require more than one transformation or enzyme.

### Step 3: Analyze the third reaction - Phosphoenolpyruvic Acid to Pyruvic Acid
- This reaction is the last step of glycolysis.
- It is catalyzed by the enzyme pyruvate kinase.
- This reaction converts phosphoenolpyruvic acid directly to pyruvic acid.
- **Conclusion**: This is a single-step process.

**Hint**: Check if the reaction can be completed in one enzymatic step.

### Step 4: Analyze the fourth reaction - Succinyl-CoA to Succinate
- This reaction is also part of the Krebs cycle.
- It is catalyzed by the enzyme succinyl-CoA synthetase.
- This reaction converts succinyl-CoA directly to succinate.
- **Conclusion**: This is a single-step process.

**Hint**: Determine if the reaction involves a direct conversion without intermediate products.

### Final Conclusion
After analyzing all the options, the only reaction that is a multi-step process is **Fumarate to Oxaloacetate**.

### Answer:
The multi-step process is **Fumarate to Oxaloacetate** (Option B).