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 |
|---|---|---|---|
| 83131 | 2020-12-14 01:11:29 | 71.53 | 96% |
| 70517 | 2020-05-24 15:59:40 | 68.18 | 96% |
| 60239 | 2019-09-11 09:28:27 | 68.82 | 96% |
| 57112 | 2019-06-16 19:51:20 | 82.32 | 96% |
| 53042 | 2019-04-22 12:46:00 | 87.49 | 97% |
| 52743 | 2019-04-21 20:26:41 | 82.13 | 96% |
| 51784 | 2019-03-31 21:40:38 | 81.85 | 96% |
| 44991 | 2018-12-18 17:35:09 | 85.97 | 96% |
| 36633 | 2018-10-16 06:24:48 | 71.87 | 96% |
| 34888 | 2018-09-28 00:30:50 | 72.08 | 95% |
| 31553 | 2018-09-05 15:17:59 | 79.60 | 97% |
| 28935 | 2018-08-13 14:33:11 | 84.31 | 97% |
| 26815 | 2018-07-22 20:43:30 | 73.55 | 95% |
| 19739 | 2018-05-14 21:43:27 | 79.01 | 96% |
| 14682 | 2018-04-06 19:29:13 | 75.54 | 96% |
| 13905 | 2018-04-03 07:47:36 | 75.47 | 97% |
| 5713 | 2017-10-23 08:54:27 | 69.51 | 96% |
| 4936 | 2017-10-17 09:14:41 | 68.87 | 96% |
| 4763 | 2017-10-16 19:59:06 | 65.47 | 97% |