What does karyokinesis refer to in the cell cycle?

Karyokinesis specifically refers to the process of nuclear division during cell division, particularly mitosis. During karyokinesis, the replicated chromosomes are separated and distributed into two new nuclei. This is a crucial step in ensuring that each daughter cell receives an identical set of chromosomes, maintaining genetic consistency across cell generations.

During karyokinesis, the chromosomes condense, align, and are pulled apart by the mitotic spindle. In contrast to karyokinesis, the division of the cytoplasm that follows is termed cytokinesis, which is a separate process essential for completing cell division. Synthesis of DNA occurs during the S phase of interphase, which precedes mitosis and is unrelated to the actual physical division of the nucleus. Cell differentiation refers to the process by which cells develop into their specialized functions and also lacks relevance to karyokinesis. Thus, the focus of karyokinesis is solely on the nuclear material's division during mitosis, making the selected answer accurate.