All multicellular organisms develop from a single cell, that is, the fertilized egg or zygote. The repeated division of a single cell produces the organism with millions of cells, organized into tissues, organ and organ systems. In unicellular organisms like Amoeba the division of the cell results in the formation of two individuals. In multicellular organisms there is constant need for tissues repair, replacement of dead cells in tissues, production of germ cells for reproduction and perpetuation of the species. In short, cell division is an essential phenomenon of life which is needed for growth, differentiation, reproduction and continuity of life in all organisms.