Extranuclear DNA refers to genetic material found outside of the nucleus of a cell. Synonyms for extranuclear DNA include mitochondrial DNA, cytoplasmic DNA, non-nuclear DNA, and organelle DNA. Mitochondrial DNA is passed down from the maternal side and is essential for energy production in cells. Cytoplasmic DNA is found in the cytoplasm of cells and is involved in various cellular processes. Non-nuclear DNA refers to DNA that is not located within the nucleus, including mitochondrial DNA and chloroplast DNA in plants. Organelle DNA refers to genetic material found within the organelles of cells, such as mitochondria and chloroplasts.