CBSE Class 9 Answered

At first the two pairs of centrioles remain in close proximity to each other, but as mitosis initiates, the original centrosome divides and the pairs are split up so that one set of centrioles is located in each of the new microtubule-organizing centers. These new centers radiate microtubules in star-shaped clusters known as asters. As the asters move to opposing poles of the cells, the microtubules, with the help of the centrioles, become organized into a spindle-shaped formation that spans the cell. These spindle fibers act as guides for the alignment of the chromosomes as they separate later during the process of cell division.