Globular head in a myosin filament is having active site for :

Options

A. ATP
B. Actin
C. Troponin
D. Both (a) and (b)

Answer

**Step-by-Step Solution:**

1. **Understanding Myosin Filament Structure**: The myosin filament is a crucial component of muscle fibers and is responsible for muscle contraction. It consists of long protein chains with globular heads.

2. **Identifying the Globular Head**: The globular head of the myosin filament is known for its ability to interact with other proteins during muscle contraction.

3. **Active Sites on the Globular Head**: The globular head contains specific active sites that are essential for its function. These active sites are responsible for binding to other molecules.

4. **ATP Binding Site**: One of the active sites on the globular head is for ATP (adenosine triphosphate). The myosin head has an ATPase enzyme that catalyzes the breakdown of ATP, which provides the energy necessary for muscle contraction.

5. **Actin Binding Site**: Another active site on the globular head is for actin, which is a protein that forms thin filaments in muscle fibers. The interaction between myosin and actin is crucial for muscle contraction.

6. **Conclusion**: The globular head of the myosin filament has active sites for both ATP and actin. Therefore, the correct answer to the question is that the globular head has active sites for both ATP and actin.

7. **Final Answer**: The correct option is D, which states that the globular head in a myosin filament has active sites for both ATP and actin.

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