A flagellum is composed of

Options

A. 1.Inclusion bodies, filament and hook
B. 2.Filament, hook and basal body
C. 3. Filament, cell wall and cell membrane
D. 4. Filament, mesosomes and basal body

Answer

To solve the question "A flagellum is composed of," we need to identify the components that make up a flagellum. Here’s a step-by-step breakdown:

### Step 1: Understand the Structure of a Flagellum
A flagellum is a long, whip-like structure that helps in the movement of certain cells, such as bacteria and sperm cells. It is important to know its main components.

### Step 2: Identify the Main Parts of a Flagellum
A flagellum is composed of three main parts:
1. **Filament**: This is the long, helical structure that extends from the surface of the cell. It is responsible for the actual movement.
2. **Hook**: This is a curved structure that connects the filament to the basal body. It acts as a flexible joint.
3. **Basal Body**: This is the structure that anchors the flagellum to the cell wall and membrane. It is also responsible for the rotation of the flagellum.

### Step 3: Analyze the Options Given
Now, let's look at the options provided in the question:
1. Individual bodies, filament, and the hook
2. Filament, hook, and basal body
3. Filament, cell wall, and cell membrane
4. Filament, mesosomes, and basal body

From our understanding:
- The first option incorrectly mentions "individual bodies."
- The third option incorrectly includes "cell wall" and "cell membrane," which are not parts of the flagellum itself.
- The fourth option incorrectly mentions "mesosomes," which are not related to the flagellum.

### Step 4: Select the Correct Answer
The only option that accurately lists the components of a flagellum is:
**Option 2: Filament, hook, and basal body.**

### Conclusion
Thus, the correct answer to the question "A flagellum is composed of" is **Option 2: Filament, hook, and basal body.**

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