What happens to chromosomes during telophase?

During telophase, the chromosomes undergo a critical transition as the cell prepares to complete division. This phase marks the end of nuclear division, and the chromosomes, which have been tightly packed and visible during earlier phases, begin to relax and decondense back into a less compact form known as chromatin. This transition is essential as it allows the genetic material to become more accessible for transcription and other cellular processes in the daughter cells.

As the chromosomes decondense, the nuclear envelope reforms around each set of separated sister chromatids, leading to the formation of two distinct nuclei within the cell. This is a vital step in ensuring that each daughter cell will have the appropriate genetic material to function properly after division.

In contrast, the options related to alignment at the cell's equator, condensation into chromatids, or replication do not occur during telophase. Aligning occurs during metaphase, condensation happens during prophase, and replication of chromosomes takes place during the S phase of the cell cycle, prior to mitosis. Thus, understanding telophase's role in returning chromosomes to a chromatin state reinforces the cell's preparation for subsequent growth and function after division.