Magnesium is an activator for

Options

A. ribulose bis-phosphate carboxylase oxygenase
B. phosphoenol pyruvate carboxylase
C. alcohol dehydrogenase
D. more than one

Answer

To solve the question "Magnesium is an activator for," we need to analyze the options provided and identify which enzymes Magnesium acts as an activator for.

### Step-by-Step Solution:

1. **Understanding the Role of Magnesium**:
- Magnesium (Mg²⁺) is known to be an essential divalent cation that plays a crucial role in various biochemical processes. It acts as a cofactor for several enzymes.

2. **Analyzing the Options**:
- **Option A**: Ribulose bisphosphate carboxylase/oxygenase (Rubisco) - This enzyme is involved in the Calvin cycle of photosynthesis and requires Magnesium as a cofactor.
- **Option B**: Phosphoenolpyruvate carboxylase (PEP carboxylase) - This enzyme catalyzes the conversion of phosphoenolpyruvate to oxaloacetate and also requires Magnesium as an activator.
- **Option C**: Alcohol dehydrogenase - This enzyme primarily requires zinc as a cofactor and does not depend on Magnesium.
- **Option D**: More than one - Since both Rubisco and PEP carboxylase require Magnesium, this option suggests that Magnesium activates more than one enzyme.

3. **Identifying the Correct Answer**:
- Since both Rubisco (Option A) and PEP carboxylase (Option B) are activated by Magnesium, the correct answer is **Option D: More than one**.

### Final Answer:
The correct option is **D. More than one**.

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