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Cell division is a process in which living cells proliferate from one cell to two cells. Cells before division are called mother cells, and new cells formed after division are called daughter cells. Generally, it includes two steps: nuclear division and cytoplasmic division. In the process of nuclear division, the mother cell transfers genetic material to the daughter cell.
In unicellular organisms, cell division is the reproduction of individuals, while in multicellular organisms, cell division is the basis of individual growth, development and reproduction. 1855, the German scholar R.Virchow put forward the famous conclusion that "all cells come from cells", that is, all cells of an individual are produced by the division of primitive cells, and there is no evidence that there are other ways of cell reproduction besides cell division.
It mainly causes cell division, induces bud formation and promotes bud growth. For tobacco pith or stem segments cultured in tissue, cytokinin can make pith cells that have no ability to divide again. This phenomenon has been used in the bioassay of cytokinin. The differentiation of stem segments is usually regulated by the ratio of cytokinin to auxin.
When the concentration ratio of cytokinin to auxin is high, the formation of buds can be induced; Instead, it tends to promote rooting. If cytokinin is applied locally to the inhibited axillary buds or auxin with a certain concentration is applied to the lateral buds, the inhibition of the apical lateral buds (i.e. apical dominance) can be relieved. Natural tufted plants (rosettes) or plants with "witches' broom disease" due to diseases often contain more cytokinins.