Mitochondria and chloroplasts display similarities with bacteria that led to the endosymbiont theory. This theory states that an early ancestor of eukaryotic cells engulfed an oxygen-using non-photosynthetic prokaryotic cell. Eventually, the engulfed cell formed a relationship with the host cell in which it was enclosed, becoming an endosymbiont, a cell living within another cell. Indeed, over the course of evolution, the host cell and its endosymbiont merged into a single organism, a eukaryotic cell with a mitochondrion. At least one of these cells may have then taken up a photosynthetic prokaryote, becoming the ancestor of eukaryotic cells that contain chloroplasts.
Game | Time | WPM | Accuracy |
---|---|---|---|
15437 | 2019-02-26 21:53:26 | 142.50 | 98% |
8413 | 2018-09-08 03:15:31 | 124.30 | 96% |
4487 | 2018-06-04 01:15:04 | 132.59 | 97% |
55 | 2018-02-16 13:38:52 | 137.27 | 98% |