G 0 does not exist in normal somatic cells. S - the time of DNA synthesis. G 2 - DNA synthesis is complete, waiting for the signal to start mitosis. Prophase - mitosis is initiated, chromosomes are condensing and attaching to the centrosome via the microtubules and kineticores. Telophase - the physical dividing of the cell itself.
Nuclear envelopes form around the two new nuclei.
The best way to see and understand the relationships between all of the components is to add the TIME dimension. Fertilization - shows the first two divisions in a developing sea urchin embryo. Unequal - shows how an unequal cell division can happen by an unequal division of the centrosome. Insect - in the fruit fly egg, mitosis is different. The egg is too big to divide at each division and fruit flies are protostomes.