Activators of RuBisCo, PEP and nitrogenase are

Options

A. Zn & Mo
B. Cd and K
C. Mg and N
D. Mg & Mo

Answer

To solve the question regarding the activators of RuBisCo, PEP, and nitrogenase, we will follow these steps:

### Step 1: Understand the Enzymes
- **RuBisCo**: The full name is ribulose bisphosphate carboxylase/oxygenase. It is a crucial enzyme in the process of photosynthesis, specifically in the Calvin cycle, where it catalyzes the carboxylation of ribulose bisphosphate (RuBP).
- **PEP**: This stands for phosphoenolpyruvate, which is an important intermediate in several metabolic pathways, including glycolysis and gluconeogenesis.
- **Nitrogenase**: This enzyme is responsible for the fixation of atmospheric nitrogen (N2) into ammonia (NH3), a process essential for nitrogen metabolism in plants.

### Step 2: Identify the Activators
- **For RuBisCo**: Magnesium ions (Mg²⁺) are known to be essential for the activation of RuBisCo. They help in the proper functioning of the enzyme.
- **For PEP**: Similar to RuBisCo, magnesium ions also play a role in the activation of enzymes involved in the metabolism of phosphoenolpyruvate.
- **For Nitrogenase**: Molybdenum (Mo) is a critical component for the nitrogenase enzyme, as it is a part of the active site of the enzyme that facilitates nitrogen fixation.

### Step 3: Combine the Activators
Based on the information gathered:
- The activator for RuBisCo is Magnesium (Mg²⁺).
- The activator for PEP is also Magnesium (Mg²⁺).
- The activator for Nitrogenase is Molybdenum (Mo).

### Conclusion
Thus, the activators of RuBisCo, PEP, and nitrogenase are Magnesium and Molybdenum.

**Final Answer**: Magnesium and Molybdenum.

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