What happens during telophase of mitosis?

• A. Sister chromatids are separated
• B. The nuclear envelope begins to reform
• C. Chromosome alignment occurs
• D. Cell growth occurs

Answer: (B)

During telophase of mitosis, significant processes are taking place that lead to the completion of cell division. The most notable event is that the nuclear envelope begins to reform around the separated sets of chromosomes at each pole of the cell. This is crucial because it sets the stage for the chromosomes to de-condense back into their less compact chromatin form, allowing for normal cellular function and gene expression once mitosis concludes.

The reformation of the nuclear envelope is essential for creating two distinct nuclei within the daughter cells, marking the end of the mitotic phase and transitioning into cytokinesis. As the nuclear envelopes reestablish, the mitotic spindle disassembles, and the chromosomes, which had been highly condensed and organized, start to decondense.

Understanding this process highlights why the correct answer centers on the reformation of the nuclear envelope, as it signifies the nearing completion of cell division, leading to the successful partitioning of genetic material.