There are some alternative names for the process, e.g., "karyokinesis" (nuclear division), a term introduced by Schleicher in 1878, or "equational division", proposed by August Weismann in 1887. The term "mitosis", coined by Walther Flemming in 1882, is derived from the Greek word μίτος ( mitos, "warp thread"). A few years later, he discovered and described mitosis based on those observations. In 1873, the German zoologist Otto Bütschli published data from observations on nematodes. īütschli, Schneider and Fol might have also claimed the discovery of the process presently known as "mitosis". In animal cells, cell division with mitosis was discovered in frog, rabbit, and cat cornea cells in 1873 and described for the first time by the Polish histologist Wacław Mayzel in 1875. In 1838, Matthias Jakob Schleiden affirmed that "formation of new cells in their interior was a general rule for cell multiplication in plants", a view later rejected in favour of Mohl's model, due to contributions of Robert Remak and others. In 1835, the German botanist Hugo von Mohl, described cell division in the green algae Cladophora glomerata, stating that multiplication of cells occurs through cell division. Numerous descriptions of cell division were made during 18th and 19th centuries, with various degrees of accuracy. Important exceptions include the gametes – sperm and egg cells – which are produced by meiosis.
Most human cells are produced by mitotic cell division. Most animal cells undergo a shape change, known as mitotic cell rounding, to adopt a near spherical morphology at the start of mitosis. For example, animal cells undergo an "open" mitosis, where the nuclear envelope breaks down before the chromosomes separate, whereas fungi undergo a "closed" mitosis, where chromosomes divide within an intact cell nucleus. Prokaryotic cells, which lack a nucleus, divide by a different process called binary fission. Certain types of cancer can arise from such mutations. Other errors during mitosis can induce mitotic catastrophe, apoptosis (programmed cell death) or cause mutations. Producing three or more daughter cells instead of the normal two is a mitotic error called tripolar mitosis or multipolar mitosis (direct cell triplication / multiplication). The different phases of mitosis can be visualized in real time, using live cell imaging. The rest of the cell may then continue to divide by cytokinesis to produce two daughter cells. The result is two genetically identical daughter nuclei.
During mitosis, the chromosomes, which have already duplicated, condense and attach to spindle fibers that pull one copy of each chromosome to opposite sides of the cell. These stages are preprophase (specific to plant cells), prophase, prometaphase, metaphase, anaphase, and telophase. The process of mitosis is divided into stages corresponding to the completion of one set of activities and the start of the next. The different stages of mitosis altogether define the mitotic ( M) phase of an animal cell cycle-the division of the mother cell into two daughter cells genetically identical to each other. In general, mitosis is preceded by S phase of interphase (during which DNA replication occurs) and is often followed by telophase and cytokinesis which divides the cytoplasm, organelles and cell membrane of one cell into two new cells containing roughly equal shares of these cellular components. Therefore, mitosis is also known as equational division. Cell division by mitosis gives rise to genetically identical cells in which the total number of chromosomes is maintained. In cell biology, mitosis ( / m aɪ ˈ t oʊ s ɪ s/) is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. pair of daughter-cells shortly after division nuclei preparing for division (spireme-stage)Ĭ. Onion ( Allium) cells in different phases of the cell cycle enlarged 800 diameters.ī.
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