The number of thick myofilaments (myosin) surrounding
Single thin myofilament (actin) are

Options

A. 3
B. 6
C. 2
D. 4

Answer

To find the number of thick myofilaments (myosin) surrounding a single thin myofilament (actin), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Myofilaments**:
- Myofilaments are the filaments of myofibrils, which are the contractile units of muscle fibers. There are two main types: thick myofilaments (myosin) and thin myofilaments (actin).

2. **Arrangement of Myofilaments**:
- In muscle fibers, the thick myofilaments (myosin) and thin myofilaments (actin) are arranged in a specific manner. The thick filaments are generally surrounded by the thin filaments.

3. **Counting the Myofilaments**:
- Each thin myofilament (actin) is surrounded by three thick myofilaments (myosin). This arrangement allows for effective muscle contraction as the myosin heads can attach to the actin filaments.

4. **Conclusion**:
- Therefore, the number of thick myofilaments (myosin) surrounding a single thin myofilament (actin) is **three**.

### Final Answer:
The number of thick myofilaments (myosin) surrounding a single thin myofilament (actin) is **three**.

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