The modified cell organelle involved in the formation of cilium and flagellum is

Options

A. Golgi complex
B. Centriole
C. Stigma
D. Nucleus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the modified cell organelle that is involved in the formation of cilia and flagella.

2. **Identifying the Options**: The options provided are:
- A. Golgi complex
- B. Centriole
- C. Stigma
- D. Nucleus

3. **Analyzing Each Option**:
- **A. Golgi Complex**: This organelle is primarily involved in modifying, sorting, and packaging proteins and lipids for secretion or delivery to other organelles. It is not directly involved in the formation of cilia and flagella.
- **B. Centriole**: Centrioles are cylindrical structures that play a crucial role in cell division and are also involved in the formation of cilia and flagella. They serve as the basal bodies from which cilia and flagella emerge.
- **C. Stigma**: This term generally refers to a part of a flower or an eye structure in some organisms, but it is not related to the formation of cilia and flagella.
- **D. Nucleus**: The nucleus is the control center of the cell containing genetic material, but it does not directly participate in the formation of cilia and flagella.

4. **Conclusion**: Based on the analysis, the correct answer is **B. Centriole**. Centrioles act as the organizing centers for microtubules, which are essential for the structure and function of cilia and flagella.

**Final Answer**: The modified cell organelle involved in the formation of cilium and flagellum is **B. Centriole**.

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