The separation of the sister chromatids during the cell division occurs in the anaphase in mitosis and anaphase II in meiosis.
During the anaphase in mitosis, and the anaphase II of the meiosis, the chromosomes aligned at the center of the nucleus separates and the sister chromatids of the chromosomes starts moving towards the opposite poles as the spindle fibers starts contracting.
Loss of habitat from any number of causes is the main reason for species endangerment currently.
