Wisdom of the protists; electron flow tricks for controlling cancer
(PHYSorg.com Biology)

All schoolchildren learn that the difference between eukaryotes and prokaryotes has something to do with a nucleus. This is usually around the same time they learn that the mitochondria is the powerhouse of the cell. The real difference between these two life forms, however, has more to do with how they control the flow of electrons to make their living, i.e., their electron transport chains going from donors to acceptors via redox reactions.