Bacteria divide by binary fission , a process by which one bacterium splits into two.
A coccus-shaped bacterium is usually spherical, although some appear oval, elongated, or flattened on one side. The correct form, however, should predominate. Also remember that each coccus in an arrangement represents a complete, single, one-celled organism. Small bacilli or bacilli that have just divided by binary fission may at first glance be confused for cocci so they must be observed carefully . You will, however, be able to see bacilli that have not divided and are definitely rod-shaped as well as bacilli in the process of dividing.