LM of cultured cells showing events of mitosis. The black and white images were taken with a Nomarski differential interference contrast microscope to enhance contrast of inherently transparent living cells. Fluorescent images show cells immunolabeled (red) for microtubule β-tubulin and stained blue with DAPI, an intercalating dye for DNA/chromosomes. 1000×. Anaphase. Daughter chromatids separate to opposite poles of the mitotic spindle. A cleavage furrow forms midway between poles.