Centromere is that part of chromosome where

Options

A. nicking occurs
B. chromatids are attached
C. Nucleoli are formed
D. Crossing-over takes place

Answer

**Step-by-Step Solution:**

1. **Understanding Centromere**: The centromere is a specific region of a chromosome that plays a crucial role during cell division. It is the point where two sister chromatids are joined together.

2. **Location of Centromere**: The centromere can be located at various positions on the chromosome. It is not fixed to one specific location; it can be found in the middle, towards one end, or anywhere along the chromosome.

3. **Function of Centromere**: The primary function of the centromere is to connect the sister chromatids. During cell division (mitosis or meiosis), the centromere ensures that the chromatids are pulled apart correctly to opposite poles of the cell.

4. **Role in Mitosis**: During mitosis, spindle fibers attach to the centromere through a structure called the kinetochore. This attachment is essential for the proper alignment and separation of chromosomes.

5. **Conclusion**: Based on the understanding of the centromere's structure and function, we can conclude that the centromere is the part of the chromosome where sister chromatids are attached.

**Final Answer**: The centromere is that part of the chromosome where sister chromatids are attached.

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