The question implicitly assumes that other theoretical explanations had been offered before the theory of symbiogenesis. I believe the truth is that up to a certain point around the later 60s, those active in the field were still too busy identifying constituents and properties of the plastids to think that the time was ripe to offer separate (...


My reading of that article suggests a slightly idiomatic translation as "Kill Them All." While that may be poor long-term strategy in a war amongst peoples, the point raised in this medical article is that failure to completely wipe out the enemy (pathogen, bacteria, whatever) can lead to the remaining organisms becoming resistant to the drug treatment. ...


Eukaryotic cells are defined by the presence of a nucleus (and any other organelles). Van Leeuwenhoek himself (in Opera Omnia, 1719) was the first to describe a cell nucleus, which he saw in salmon blood cells: (By the way, while mammalian red blood cells don't have a nucleus, the red blood cells of most other creatures do.)

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