Mitosis is the process by which a cell duplicates the chromosomes in its cell nucleus, in order to generate two, identical, daughter nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two daughter cells containing roughly equal shares of these cellular components. Mitosis and cytokinesis together define the mitotic (M) phase of the cell cycle, the division of the mother cell into two daughter cells, each with the genetic equivalent of the parent cell.
The process of mitosis is complex and highly regulated. The sequence of events is divided into phases, corresponding to the completion of one set of activities and the start of the next. These stages, in order from first to last, are prophase , prometaphase , metaphase, anaphase and telophase . During the process of mitosis the pairs of chromosomes condense and attach to fibers that pull the sister chromatids to opposite sides of the cell. The cell then divides in cytokinesis, to produce two identical daughter cells.
Because cytokinesis usually occurs in conjunction with mitosis, "mitosis" is often used interchangeably with "mitotic phase." However, there are many cells where mitosis and cytokinesis occur separately, forming single cells with multiple nuclei. This occurs most notably among the fungi and slime moulds, but is found in various different groups. Even in animals, cytokinesis and mitosis may occur independently. For instance, during certain stages of fruit fly embryonic development errors in mitosis can either kill a cell through apoptosis or cause mutations that may lead to cancer. The mitotic phase, M phase , of the cell cycle includes both mitosis and cytokinesis which produces two identical daughter cells.