Microtubules take part in

Options

A. Formation of spindle fibres
B. Movement of cilia and flagella
C. Both A and B
D. Cyclosis

Answer

**Step-by-Step Solution:**

1. **Understanding Microtubules**: Microtubules are structural components of the cell, made up of polymers of tubulin protein, specifically alpha and beta tubulin.

2. **Formation of Microtubules**: These tubulin proteins polymerize to form protofilaments. Typically, 13 to 20 protofilaments come together in a hollow tubular arrangement to form a microtubule.

3. **Functions of Microtubules**: Microtubules have several important functions:
- They are part of the cytoskeleton, providing structural support and shape to the cell.
- They play a crucial role in the formation of spindle fibers during cell division. Spindle fibers are essential for the separation of chromosomes.
- Microtubules are also involved in the movement of cilia and flagella, which are hair-like structures that aid in cell motility.

4. **Evaluating the Options**:
- **Option A**: Formation of spindle fibers - This is correct as microtubules are integral in forming spindle fibers.
- **Option B**: Movement of cilia and flagella - This is also correct since microtubules are essential for the function of these structures.
- **Option C**: Cyclosis - This option is incorrect because cyclosis (the movement of cytoplasm within the cell) is facilitated by microfilaments, not microtubules.
- **Option D**: Both A and B - This is correct as both functions mentioned in options A and B are performed by microtubules.

5. **Conclusion**: The correct answer is **Both A and B**.

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