Enzyme with dual nature is

Options

A. Hexokinase
B. RuBisCO
C. RuBP
D. Pyruvic carboxylase

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for an enzyme that exhibits dual nature. This means the enzyme can catalyze two different reactions or processes.

2. **Identifying the Options**: The options provided are:
- A) Hexokinase
- B) Rubisco (Ribulose 1,5-bisphosphate carboxylase)
- C) ReBP (Ribulose 1,5-bisphosphate)
- D) Pyruvic carboxylase

3. **Analyzing Each Option**:
- **Hexokinase**: This enzyme catalyzes the phosphorylation of glucose to glucose-6-phosphate. It does not exhibit dual nature.
- **Rubisco (Ribulose 1,5-bisphosphate carboxylase)**: This enzyme catalyzes two reactions:
- Carboxylation of ribulose 1,5-bisphosphate (RuBP) to produce 3-phosphoglycerate (PGA), a 3-carbon compound.
- Oxygenation of RuBP, leading to the production of phosphoglycolate, a 2-carbon compound, which initiates photorespiration.
- **ReBP (Ribulose 1,5-bisphosphate)**: This is a substrate for Rubisco and does not function as an enzyme.
- **Pyruvic carboxylase**: This enzyme catalyzes the conversion of pyruvate to oxaloacetate but does not exhibit dual nature.

4. **Conclusion**: The only enzyme that shows dual nature by catalyzing both carboxylation and oxygenation reactions is Rubisco. Therefore, the correct answer is option B) Rubisco.

5. **Final Answer**: The enzyme with dual nature is **Rubisco (Ribulose 1,5-bisphosphate carboxylase)**.

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