There are two types of chromatin . Euchromatin is the less compact DNA form , and contain genes that are frequently expressed by the cell . The other type , heterochromatin , is the more compact form , and contain DNA that is infrequently transcribed . This structure is further categorized into facultative heterochromatin , consisting of genes that are organized as heterochromatin only in certain cell types or at certain stages of development , and constitutive heterochromatin that consist of chromosome structural components such as telomeres and centromeres . During interphase the chromatin organize itself into discrete individual patches , called chromosome territories . Active genes , which are generally found in the euchromatic region of the chromosome , tend to be located towards the chromosome 's territory boundary .