Final answer:
The correct answer is option e. The mitotic spindle, which is responsible for the equal separation of chromosomes into two new cells, arises from the centrosomes. Kinetochore microtubules bind to the centromere of chromosomes to facilitate their segregation during cell division.
Step-by-step explanation:
Function of the Mitotic Spindle in Chromosome Separation
The mitotic spindle is an essential structure during the cell division process known as mitosis. It is responsible for the equal distribution of chromosomes into two sets. The portion of the cytoskeleton that enables the chromosomes to be separated is the mitotic spindle. The mitotic spindle arises from structures called the centrosomes, which are the main microtubule organizing centers of the cell.
During mitosis, particularly in the prophase stage, the centrosomes move to opposite poles of the cell. Microtubules, which compose the mitotic spindle, extend between the centrosomes, pushing them farther apart. The chromosomes, which are already duplicated and condensed into sister chromatids, are attached at their central region called the centromere. Here, a protein structure known as the kinetochore develops, allowing spindle microtubules to bind.
As the cell progresses through metaphase to anaphase, the attached microtubules pull the sister chromatids apart and toward opposite poles, facilitated by the shortening of kinetochore microtubules. This process ensures that each new cell receives an identical set of chromosomes, completing their segregation into two distinct new cells.