Differential interference contrast (DIC) light micrograph of mitosis (nuclear division, right) and cytokinesis (cellular division, left) in cells that have had the enzyme topoisomerase II inhibited. Topoisomerase II plays a role in the condensation of chromosomes (dark purple) prior to mitosis, the formation of two daughter nuclei from one parent nucleus. At right the cell is in the metaphase stage of mitosis, where the chromosomes should be lining up along the centre of the cell. However, inhibition of topoisomerase II has prevented complete condensation of the chromosomes. In the cell at left incomplete condensation has lead to the incomplete segregation of the chromosomes, which are still attached as the cell is dividing. Giemsa stain.