endosymbiont theory


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endosymbiont theory

[‚en·dō′sim·bē‚änt ‚thē·ə·rē]
(cell and molecular biology)
A theory that the mitochondria of eukaryotes and the chloroplasts of green plants and flagellates originated as free-living prokaryotes that invaded primitive eukaryotic cells and become established as permanent symbionts in the cytoplasm.
References in periodicals archive ?
Batten concludes his critique of the endosymbiont theory by insisting that
This convenient dismissal of the endosymbiont theory ignores the deep molecular similarities between modern mitochondria and chloroplasts and members of specific groups of extant eubacteria; similarities that have little to do with their chemistry.
Not everyone is enthusiastic about the endosymbiont theory.