Question

Explain the endosymbiotic theory of the origin of eukaryotic cells.

Answer 1

Hey there,

The endosymbiotic theory concerns the mitochondria, plastids (e.g. chloroplasts), and possibly other organelles of eukaryotic cells. According to this theory, certain organelles originated as free-living bacteria that were taken inside another cell as endosymbionts. Heterotrophic bacteria engulfed other bacteria (such as cyanobacteria) and through time and natural selection, the endosymbiont became a permanent part of the host cell.

Can you give more info on what's troubling you though? Then I can provide perhaps a better reply. I could list some evidence (there's plenty!) supporting this theory, as well.