Cilia and fiagella are outgrowth of

Options

A. Cell wall
B. Cell membrane
C. Nucleus
D. ER

Answer

**Step-by-Step Solution:**

1. **Understanding Cilia and Flagella**: Cilia and flagella are hair-like structures that extend from the surface of many eukaryotic cells. They play a crucial role in movement and locomotion.

2. **Identifying the Origin**: To answer the question, we need to determine what these structures are outgrowths of. Cilia and flagella are not part of the cell wall, nucleus, or endoplasmic reticulum (ER).

3. **Cell Membrane Connection**: Cilia and flagella are extensions of the cell membrane. They are formed from the cytoskeleton, specifically microtubules, which are organized in a specific arrangement.

4. **Composition**: Both cilia and flagella are composed of microtubules arranged in a "9+2" structure, meaning there are nine pairs of microtubules surrounding two central microtubules.

5. **Functionality**: The primary function of cilia and flagella is to facilitate movement. Cilia can move fluids over the surface of the cell, while flagella are typically used for the movement of the cell itself.

6. **Conclusion**: Therefore, the correct answer to the question "Cilia and flagella are outgrowths of" is the cell membrane.

**Final Answer**: Cilia and flagella are outgrowths of the cell membrane.

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