What is the function of spindle fibers during mitosis?

The function of spindle fibers during mitosis is primarily to assist in the separation of sister chromatids. Spindle fibers are crucial components of the mitotic spindle, which forms during cell division. They are composed of microtubules that grow out from the centrosomes at the poles of the cell.

As the cell progresses through the phases of mitosis, specifically during metaphase, these fibers attach to the kinetochores of each sister chromatid, aligning the chromosomes at the cell's equatorial plane. During anaphase, the spindle fibers shorten, pulling the sister chromatids apart toward opposite poles of the cell. This ensures that each daughter cell receives an identical set of chromosomes.

The other functions mentioned in the options do not pertain to spindle fibers. While the nuclear membrane disassembles during prophase and does reform at the end of telophase, this process is not related to spindle fiber function. The coiling of chromatin is related to the organization of DNA for cell division, but it does not involve spindle fibers. The reforming of the nucleolus occurs after mitosis concludes, and is similarly not associated with spindle fiber activity. Thus, the role of spindle fibers specifically centers on the separation and movement of sister chromat