The main functions include the attachment of sister chromatids, and it is the site for attachment of spindle fibre. Centromeres help in the proper alignment and segregation of the chromosomes during the process of cell division in eukaryotic cells. Related Theory The main component of the centromere is the kinetochore and DNA associated proteins. Centromeres are densely packed with the heterogeneous domain capped by the trilaminar kinetochore. The DNA of the centromeres is normally in a heterochromatin state, which is required for attachment of sister chromatids mediated by cohesin complex and also for the separation during anaphase.