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 |
---|---|---|---|
12608 | 2020-06-25 12:08:02 | 85.14 | 97% |
8862 | 2020-02-21 23:16:23 | 82.70 | 97% |
8769 | 2020-01-11 12:34:24 | 87.22 | 98% |
4459 | 2018-04-13 13:06:21 | 73.40 | 97% |
3256 | 2017-11-05 05:10:25 | 66.90 | 95% |