Which of the following is an ATPase enzyme?

Options

A. 1. Troponin
B. 2. Light meromyosin
C. 3. Tropomyosin
D. 4. Heavy meromyosin'

Answer

To determine which of the following is an ATPase enzyme, we will analyze each option provided:

1. **Troponin**:
- Troponin is a complex of proteins found in skeletal and cardiac muscle fibers. It plays a crucial role in muscle contraction by regulating the interaction between actin and myosin. However, it does not have ATPase activity.
- **Conclusion**: Incorrect option.

2. **Light Meromycin**:
- Light meromycin is a fragment of myosin, which is a motor protein involved in muscle contraction. It does not exhibit ATPase activity on its own.
- **Conclusion**: Incorrect option.

3. **Tropomyosin**:
- Tropomyosin is a protein that binds to actin filaments and helps regulate muscle contraction. It does not have ATPase activity.
- **Conclusion**: Incorrect option.

4. **Heavy Meromycin**:
- Heavy meromycin is a part of the myosin molecule and is known to exhibit ATPase activity. It plays a significant role in muscle contraction by hydrolyzing ATP to provide the energy necessary for muscle movement.
- **Conclusion**: Correct option.

**Final Answer**: The ATPase enzyme among the options provided is **Heavy Meromycin (Option 4)**.

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