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adj. Of or pertaining to endosymbiosis.

adj. That lives within a body or cells of another organism. Forming an endosymbiosis.

"What's interesting about this study is that it challenges a widely held hypothesis that Eucarya arose out of the fusion of a bacterium with an archaeon (also known as the endosymbiotic origin of the nucleus, not to be confused with the endosymbiotic origin of mitochondria and chloroplasts)."

symbiosis    endosymbiotic theory    endosymbiosis    endosymbiont    symbiotic