Mitosis: In Summary In prometaphase, kinetochores appear at the centromeres and mitotic spindle microtubules attach to kinetochores. In metaphase, chromosomes are lined up and each sister chromatid is attached to a spindle fiber. In anaphase, sister chromatids (now called chromosomes) are pulled toward opposite poles.Click to see full answer. In this way, what phase do spindle fibers attach to the homologous chromosome pairs? anaphase I Likewise, what part of the chromosome attaches to spindle? The two sister chromatids of a chromosome are connected in the center of the chromosome, called the centromere. Microtubules called spindle fibers begin extending from the centrosomes and begin to attach to the kinetochores of the chromosomes, which are at the centromeres (centers) of the chromosomes. Besides, what do spindle fibers attach to during mitosis? The movement of chromosomes is facilitated by a structure called the mitotic spindle, which consists of microtubules and associated proteins. Spindles extend from centrioles on each of the two sides (or poles) of the cell, attach to the chromosomes and align them, and pull the sister chromatids apart.Where do spindle fibers attach during meiosis?The spindle fibers from the other side of the cell attach to the other sister chromatids of the chromosome. They attach at a point called the kinetochore, which is a disk or protein that is on each side of the centromere. The spindle fibers will move the chromosomes until they are lined up at the spindle equator.