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Cell division
From Citizendium, the Citizens' Compendium
Cell division is the process by which a parent cell divides into two or more daughter cells and is usually an integral part of the cell cycle. This type of cell division is called mitosis where the daughter cells are capable of dividing again. In another type of cell division (meiosis) present only in eukaryotes, a cell is permanently transformed into a gamete and cannot divide again until fertilization.
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Prokaryotic cell division
Eukaryotic cell division
Interphase
Interphase is the cell phase between cell division. The genetic material containing DNA is in the chromatin form instead of being formed into individual chromosomes.
Mitosis
Mitosis is the common or usual cell division in which all the chromosomes of a parent cell are reproduced (doubled) and a complete set of identical chromosomes is provided to each daughter cell. Mitosis typically involves a parent diploid cell dividing into two daughter diploid cells in eukaryotic cell division.
The stages of mitotic division
Prophase
Metaphase
The chromosomes attached to the spindle are moved to the equatorial plane of the cell
Anaphase
Telophase
Meiosis
Meiosis is a special form of cell division to produce special daughter cells called gametes, which have only half the number of common cells, which are diploid cells. In meiosis, the chromosomes are not doubled as in mitosis, but simply distributed among the two daughter cells, such that each gamete has half the number of chromosomes as the parent cell. Meiosis involves a parent diploid cell dividing into two daughter haploid cells, each of which have one set of a pair of two matching sets of chromosomes such that the gamete haploid cells can later be combined in fertilization to produce a full diploid cell. Depending on the number of chromosomes in each cell, the variety of resulting gamete chromosome "random" combinations can be large, which can then result in a vast variety of fertilized cells when gametes are recombined. Essentially, this recombination of chromosomes in a vast variety of combinations becomes the basis of sexual reproduction, resulting in genetic diversity within a species.
