Index >>Cytoplasmic or Extranuclear Inheritance >> Cytoplasmic or Extranuclear Inheritance

The eukaryotic cells possess a main complement of chromosomes in the nucleus and extra-DNA molecules or chromosomes in their mitochondria and chloroplasts. Qualifying also as extra-hereditary elements are certain viruses bacteria and algae that take up residence within other cells and often aquire a permanent and mutually dependent relationship with their hosts (endosymbiosis). Finally, properties of certain eukaryotic cells suggest that their surfaces may possess genetic information that can be modified by the environment and inherited independently of the main chromosomes. These cytoplasmic extra-nuclear genes or DNA molecules of plasmids, mitochondria, chloroplasts, endosymbionts and cellular surfaces have a characteristic pattern of inheritance which does not resemble with that of genes of nuclear chromosomes and is known by different terms such as non-Mendelian. Non-chromosomal uniparental, maternal, extra-chromosomal, cytoplasmic and extra-nuclear inheritance.