Final answer:
During anaphase of mitosis, the sister chromatids separate and move to opposite poles due to the shortening of spindle fibers.
Step-by-step explanation:
Anaphase is the phase of mitosis during which the two copies of chromosomes, called chromatids, separate and move to opposite poles as the spindle fibers pull them. During anaphase, the centromeres divide and the sister chromatids are pulled apart by the shortening of the spindle fibers. One sister chromatid moves to one pole of the cell, and the other sister chromatid moves to the opposite pole.
Mitosis is a process of cell division in which a single cell divides to produce two genetically identical daughter cells. This type of cell division is crucial for growth, development, tissue repair, and maintenance of the body's cells. Mitosis occurs in somatic cells, which are all cells in the body except for the reproductive cells (gametes) – sperm and egg cells.