-Present-day mitochondria and chloroplasts probably evolved as a consequence of early endosymbiosis: the ancestor of the eukaryotic cell engulfed a bacterium, and the bacterium continued to function within the host cell. 1) What is the Endosymbiont theory? What is the evidence supporting this theory?

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The evidence suggests that these chloroplast organelles were also once free-living bacteria.

Explanation:

The endosymbiotic event that generated mitochondria must have happened early in the history of eukaryotes, because all eukaryotes have them.

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if your own plato the answer is b. the fern transitioned from sporophyte generation to gametophyte generation.