Spindle fibers attach on to

Options

A. Kinetochore of the chromosome
B. Centromere of the chromosome
C. Kinetosome of the chromosome
D. Telomere of the chromosome

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where spindle fibers attach during cell division. This is a critical aspect of the cell cycle, particularly during mitosis.

2. **Identifying Key Terms**: The options provided are:
- Kinetochore
- Kinetomer
- Kinetosome
- Telomer

3. **Defining Spindle Fibers**: Spindle fibers are structures that form during cell division. They are essential for the movement of chromosomes.

4. **Role of the Centromere**: The centromere is the region of a chromosome where the two sister chromatids are joined together. It plays a crucial role in the attachment of spindle fibers.

5. **Introduction of Kinetochore**: The kinetochore is a specialized structure that forms at the centromere during cell division. It is responsible for the attachment of spindle fibers to the chromosome.

6. **Formation of Spindle Fibers**: During prophase of mitosis, spindle fibers are formed, and the kinetochore produces fibers that attach to the spindle fibers.

7. **Conclusion**: The spindle fibers attach to the kinetochore of the chromosome. Therefore, the correct answer is "kinetochore of the chromosome."

**Final Answer**: Spindle fibers attach to the kinetochore of the chromosome.

---