Two events then occur: first, the proteins that bind sister chromatids together are cleaved. These sister chromatids now become separate daughter chromosomes, and are pulled apart by shortening kinetochore microtubules and move toward the respective centrosomes to which they are attached. The cleaved centromeres go first while the chromatids trail behind. They all look like they're trying to grab at their partners, because they become shaped like a V.
Next, the polar microtubules elongate, pulling the centrosomes (and the set of chromosomes to which they are attached) apart to opposite ends of the cell. The force that causes the centrosomes to move towards the ends of the cell is still unknown, although there is a theory that suggests that the rapid assembly and breakdown of microtubules may cause this movement. At the end of anaphase the kinecticore microtubules all degrade.
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