Mitosis is a process of cell division that produces two genetically identical daughter cells. The four phases of mitosis are prophase, metaphase, anaphase, and telophase. Some textbooks list five phases, breaking prophase into an early phase (called prophase) and a late phase (called prometaphase) . The phases occur in strict sequential order, and cytokinesis, the process of dividing the cell contents to make two new cells, starts in anaphase or telophase. Here is a brief description of each phase:
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Prophase: Chromosomes condense and become visible, spindle fibers emerge from the centrosomes, the nuclear envelope breaks down, and the nucleolus disappears.
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Metaphase: Chromosomes line up along the metaphase plate (center of the cell) .
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Anaphase: Sister chromatids are pulled to opposite poles of the cell.
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Telophase: Nuclear envelope reforms, chromosomes unfold into chromatin, and cytokinesis can begin.
It is important to note that mitosis is not individual phases, but a continuous process that can be thought of as a movie.
