Deoxyribonucleic acid. Conceptual artwork of DNA (deoxyribonucleic acid) spelt out with fluoresence micrographs of anaphase stage cells. Anaphase is a stage of mitosis (nuclear division). During mitosis two daughter nuclei are formed from one parent nucleus. At anaphase, sister chromatids are moved to separate poles of the cell by microtubules (purple). Chromatids consist of DNA (white). Two identical chromatids make up one chromosome. Microtubules, part of the cell's cytoskeleton, grow from each pole of the cell and attach to the chromosomes. The microtubules then contract, pulling the chromatids to opposite poles. The cell then divides to form two new cells.