mitotic


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mi·tot·ic

(mī-tot'ik), Avoid the jargonistic use of this word as a synonym of neoplastic or malignant.
Relating to or marked by mitosis.

mitotic

adjective Referring to mitosis.

mi·tot·ic

(mī-tot'ik)
Relating to or marked by mitosis.

mitosis

(mi-to'sis) (mi-to'sez?) plural.mitoses [Gr. mitos, thread + -osis]
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MITOSIS
A type of cell division of somatic cells in which each daughter cell contains the same number of chromosomes as the parent cell. Mitosis is the process by which the body grows and dead somatic cells are replaced. Mitosis is a continuous process divided into four phases: prophase, metaphase, anaphase, and telophase. mitotic (mi-tot'ik), adjective See: illustration; meiosis

Prophase: The chromatin granules of the nucleus stain more densely; the DNA strands coil extensively and become visible as chromosomes. These first appear as long filaments, each consisting of two identical chromatids, the result of DNA replication. Each pair of chromatids is joined at a region called the centromere, which may be central or toward one end. As prophase progresses, the chromosomes become shorter and more compact and stain densely. The nuclear membrane and the nucleoli disappear. At the same time, the centriole divides and the two daughter centrioles, each surrounded by a centrosphere, move to opposite poles of the cell. They are connected by fine protoplasmic fibrils, which form an achromatic spindle.

Metaphase: The chromosomes (paired chromatids) arrange themselves in an equatorial plane midway between the two centrioles.

Anaphase: The chromatids (now called daughter chromosomes) diverge and move toward their respective centrioles. The end of their migration marks the beginning of the next phase.

Telophase: The chromosomes at each pole of the spindle uncoil, the reverse of prophase, each becoming a long, loosely spiraled thread. The nuclear membrane re-forms and nucleoli reappear. Outlines of chromosomes disappear, and chromatin appears as granules scattered throughout the nucleus and connected by a lightly staining net. The cytoplasm divides (cytokinesis), resulting in two complete cells. This is accomplished in animal cells by constriction in the equatorial region; in plant cells, a cell plate develops in the same region and becomes the new cell wall. The period between two successive divisions is called interphase.

Mitosis is of particular significance in that genes are distributed equally to each daughter cell, and the diploid number of chromosomes is maintained in all somatic cells of an organism.

heterotypic mitosis

The first or reduction division in the maturation of germ cells.

homeotypic mitosis

The second or equational division in the maturation of germ cells.
illustration
References in periodicals archive ?
These findings were surprising, as during the development of epithelial tissues Par3 was considered to serve tissue function rather through orienting mitotic spindles.
Chemotherapy may be recommended as part of the treatment protocol in cases where the MCT has metastasized or has been rated as high-grade or Grade III, as well as those with a positive c-Kit mutation result, dirty margins, high scores on either the prognostic panel or mitotic index, or presenting with multiple tumors.
Using the nematode Caenorhabditis elegans as a model system, Tamara Mikeladze-Dvali and her colleagues screened a random collection of genetic mutants for mutations that disrupt the formation of the mitotic spindle.
No universally advocated grading system exists, but high-grade PCA tends to demonstrate locally aggressive features, cytologic atypia, high mitotic rate, necrosis, and absence of papillary features.
For practical purposes, Ki-67 LI should be calculated in surgical specimens by counting at least 2000 consecutive tumor cells in hot spot fields at X40 lens or 2 [mm.sup.2] for consistency with histologic classification, possibly in the same tumor areas as those used for assessing mitotic count.
Today's systems offer fully automated identification of immunofluorescence patterns on HEp-2 cells, including nuclear, cytoplasmic, mitotic, and, importantly, mixed patterns.
In addition, our results showed that some rare ANA patterns, particularly mitotic patterns may be associated with non autoimmune conditions.
According to [16], the first effect caused by Al in plants is the reduction of root growth, causing inhibition of stretching, cell expansion and mitotic index.
Mitotic count was determined from 200 adjacent highpower fields (HPFs) within the most active area of karyomitosis.
For that, the antioxidant enzymatic battery was analyzed, together with flow cytometric, micronuclei, mitotic aberrations, and comet assays.
Following univariate Cox regression modeling, only stage I disease and low-to-intermediate mitotic index were significantly associated with improved survival.