The process by which a cell divides to form two daughter cells, each having a nucleus containing the same number of chromosomes, with the same genetic composition, as that of the mother cell. The changes that occur in the structure of the chromosomes and in the cytoplasm are clearly visible with a light microscope and form a sequence of stages; *prophase
, and *cytokinesis
. As a result of mitotic divisions, all the cells of the sporophyte of higher plants have diploid nuclei that are genetically identical to that of the fertilized egg cell. Similarly all the cells of a gametophytic plant body have haploid nuclei genetically identical to the gamete from which the plant arose.