The filament in bacterial flagellum can rotate by

Options

A. `360^(@)`
B. `60^(@)`
C. `120^(@)`
D. `80^(@)`

Answer

### Step-by-Step Solution:

1. **Understanding Bacterial Flagellum**: The bacterial flagellum is a helical structure made up of a protein called flagellin. It is responsible for the motility of bacteria.

2. **Attachment to the Cell**: The base of the flagellum is attached to a structure called the basal body, which is located near the cell surface and is enclosed within the cell envelope.

3. **Rotation Mechanism**: The flagellum can rotate in two directions: clockwise and counterclockwise. This rotation is similar to the motion of a propeller.

4. **Direction of Movement**: When the flagellum rotates, it causes the bacteria to move in a specific direction. The rotation can be described as a full 360-degree turn.

5. **Conclusion**: Based on the information, the filament of the bacterial flagellum can rotate by 360 degrees, which is the correct answer.

### Final Answer:
The filament in the bacterial flagellum can rotate by **360 degrees**.

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