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 |
|---|---|---|---|
| 85795 | 2020-08-01 09:46:14 | 86.02 | 96% |
| 80505 | 2020-01-25 10:55:27 | 87.70 | 95% |
| 74100 | 2019-08-24 08:31:39 | 92.16 | 95% |
| 73575 | 2019-08-12 04:57:08 | 96.69 | 97% |
| 71826 | 2019-06-29 09:42:38 | 91.34 | 96% |
| 69119 | 2019-04-08 10:13:01 | 89.29 | 96% |
| 63294 | 2019-01-22 04:07:30 | 88.39 | 96% |
| 58355 | 2018-11-18 09:17:24 | 103.78 | 98% |
| 58354 | 2018-11-18 09:13:25 | 95.92 | 96% |
| 58072 | 2018-11-13 07:11:20 | 94.16 | 97% |
| 57964 | 2018-11-10 15:54:45 | 96.87 | 97% |
| 57734 | 2018-11-07 00:49:15 | 96.00 | 97% |
| 57729 | 2018-11-07 00:43:04 | 92.67 | 97% |
| 57647 | 2018-11-04 09:07:25 | 93.06 | 97% |
| 57621 | 2018-11-03 06:47:25 | 94.12 | 97% |
| 46558 | 2018-01-19 02:30:30 | 92.92 | 97% |
| 43596 | 2017-11-27 05:45:53 | 91.17 | 98% |
| 42223 | 2017-11-10 06:06:44 | 85.70 | 96% |
| 39936 | 2017-10-12 05:39:18 | 82.85 | 97% |
| 39935 | 2017-10-12 05:37:17 | 77.26 | 95% |