During mitosis, new nuclear membranes form around the chromatids that were split during the anaphase stage of the process. The nuclear membrane of the original nucleus dissolves during the earlier prophase stage of the mitosis.
Mitosis is a process in the life cycle of a cell wherein it divides to create exact duplicates of itself. This process is important for the growth, regeneration and reproduction of most living things. The stages of mitosis are interphase, prophase, metaphase, anaphase and telophase.
The chomosomes are duplicated in in the interphase stage, and the nuclear membrane dissolves in the prophase stage as the cell prepares to divide. During metaphase, the chromosomes align at the metaphase plate. The chromosomes then split at the anaphase stage and the chromatids become two new chromosomes that are exact duplicates of the parent chromosome. New nuclear membrane forms around the two new chromosomes in the telophase stage, completing the mitosis process.