Prophase: The chromosomes condense and the nuclear envelope breaks down. Centrioles move to opposites ends of the cell, forming the mitotic spindle. Metaphase: Chromosomes line up at the equator of the cell and attach to the spindle by their centromere. Anaphase: The centromeres divide, seperating each pair of sister chromatids. The mitotic spindle contracts and pulls chromatids to opposite poles of the spindle, centromere first. The chromatids have a characteristic V shape during this stage. Telophase: The chromatids reach opposite poles of the spindle and uncoil to become long & thin again. The nuclear envelope reforms around each group of chromosomes so that there are now two nuclei.