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 |
---|---|---|---|
20608 | 2019-10-19 05:48:57 | 84.01 | 97% |
16647 | 2018-12-23 09:44:55 | 85.01 | 97% |
15260 | 2018-09-30 10:54:02 | 78.81 | 97% |
10698 | 2018-07-22 02:00:15 | 82.28 | 98% |