Mitochondria are structures within the confines of cells in biological lifeforms.
Mitochondrial structure is recorded by the transporter, and is often useful for identifying remains following a transpoter accident. In 2367, Doctor Beverly Crusher compared the mitochondrial structure from the remains of Vulcan Ambassador T'Pel to that of her last transport. The discrepancies between the remains and the transporter pattern led Crusher and Lieutenant Commander Data to deduce that the remains had been replicated, indicating Romulan treachery. (TNG: "Data's Day")
The Doctor gave Naomi Wildman a lesson on cellular biology in early 2374. Mitochondria were part of the topic; Wildman likened them to "the warp core of the cell." (VOY: "Mortal Coil")
References
- DS9: "In the Cards"
- DS9: "Hippocratic Oath"