The region of the chromosome with which they attach themselves to spindle during cell division is known as……………………………

Explanation

**Step-by-Step Solution:**

1. **Understanding the Structure of a Chromosome**: A chromosome consists of two sister chromatids joined together.

2. **Identifying the Spindle Fibers**: During cell division, spindle fibers emerge from the centrosomes and play a crucial role in separating the chromatids.

3. **Locating the Attachment Point**: The spindle fibers attach to a specific region on the chromosome. This region is crucial for the movement of chromatids during cell division.

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