Nuclear dimorphism

Nuclear dimorphism is a trait that refers to a cell having two different type of nuclei in the same cell. It appears in a number of protozoa ciliates. A common example of an orgnaism that expresses nuclear dimorphism is Paramecium. The two types of nuclei it gives rise to is the macronuclei and the micronuclei. Genes are preserved and kept unexpressed in the micronuclei while genes are expressed  in the macronuclei