What is the function of the centromere during mitosis?

The centromere plays a crucial role during mitosis by holding sister chromatids together. It is the region of a chromosome where the two chromatids are joined, and this attachment is essential for the proper separation of chromatids during cell division. When cells enter mitosis, the centromere facilitates the connections to spindle fibers, which are responsible for pulling the chromatids apart towards opposite poles of the cell. This ensures that each new daughter cell receives an identical set of chromosomes.

While other options mention important cellular functions, they do not pertain directly to the role of the centromere during mitosis. DNA replication occurs during the S phase of the cell cycle, before mitosis begins, while cellular structures like the cell wall are not part of the chromosomal mechanics in mitosis. Energy generation is a function managed by mitochondria, not the centromere. Thus, the centromere's primary function in mitosis is indeed to hold chromatids together, which is vital for successful chromosome segregation and the maintenance of genetic integrity in daughter cells.