What occurs during anaphase of mitosis?

During anaphase of mitosis, the key event is the separation of sister chromatids. This process follows metaphase, where chromosomes are aligned at the cell's equatorial plane. When the anaphase stage begins, proteins that hold the sister chromatids together are cleaved, allowing the chromatids to be pulled apart toward opposite poles of the cell.

This separation ensures that each daughter cell will receive an identical set of chromosomes when the cell divides. The movement of the chromatids is facilitated mainly by the action of spindle fibers, which shorten and pull the chromatids apart.

Understanding anaphase is crucial as it is a pivotal moment in ensuring genetic stability and accuracy during the cell division process. The other processes mentioned, such as chromosome replication, disassembly of spindle fibers, and reformation of the nuclear membrane, take place at different stages of the cell cycle and are not characteristic of anaphase specifically.