- Mitochondria are inherited exclusively from the mother, present in almost all human cells.
- Around 2 billion years ago, an archaeon engulfed a bacterium, leading to a symbiotic relationship that created modern cells.
- This fusion event happened only once, and all plants, animals, and fungi descend from it.
- The engulfed bacterium belonged to the Rickettsia family, based on DNA comparisons.
- Mitochondria boosted cellular energy capacity by a factor of 1,000, enabling complex life.