What Happens During Mitosis?

During mitosis, the nucleus of an eukaryote cell splits into two. The parent cell goes through other stages of division before forming two genetically identical daughter cells, which are also able to duplicate.

There are five stages in the process of mitosis: prophase, metaphase, anaphase, telophase and cytokinesis. Prior to the process, each chromosome, which is a complex molecule that holds genetic material such as DNA and RNA, makes an exact copy of itself. During the first stage of mitosis, prophase, the cell further prepares itself for duplicating. Chromosomes condense, centrioles and asters duplicate, and the nuclear membrane begins to disintegrate.

During metaphase, the chromosomes line up in the middle of the cell. The duplicated chromosomes are connected to spindle fibers by their centromeres. Early anaphase is characterized by the splitting of the centromeres as one copy of each chromosome moves towards each pole of the cell. By the end of anaphase, the chromosomes have nearly reached their positions in their respective poles, and the cell membrane begins to separate in the center.

During telophase, nuclear membranes form around the bundles of separated chromosomes. Lastly, the center of the cell completely pinches through, and two cells are formed in a process known as cytokinesis. Cytokinesis is not technically a stage of mitosis, but it is necessary for the cells to actually physically separate from each other.