Mitochondria are organelles found within the cells of all living things. Possessing DNA different from that in the cell's nucleus, mitochondria may be the remains of a seperate organism that the nucleus absorbed into the cell shortly after life on this planet began. Opposing theories state that mitochondria deliberately entered the cell as a nucleic parasite. mitochondria generate ATP, an important source of cell power.
Based on data taken from mitochondria DNA collected from people of various ethnic backgrounds, a hypothesis was formed tracing all mitochondria to a single source: a female human in ancient Africa, identified as "Mitochondria Eve."