Define karyokinesis.

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Karyokinesis**: Karyokinesis is the process of nuclear division that occurs during the M phase of the cell cycle.

2. **M Phase Context**: The M phase, or mitotic phase, is the stage of the cell cycle where cell division takes place. It encompasses both karyokinesis (nuclear division) and cytokinesis (cytoplasmic division).

3. **Process of Karyokinesis**: During karyokinesis, the genetic material (DNA) within the nucleus condenses into distinct chromosomes. This condensation transforms the chromatin (the less organized form of DNA) into tightly packed chromosomes.

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