The Protozoa, or one-celled animals, belonged to an unknown world before the invention of the microscope. The first of these instruments enabled the early observers to see some of the larger and more conspicuous members of the group and each improvement of the microscope has enabled us to see more and more of them and to study in detail not only the structure but to follow the life-history of many of them.
Game | Time | WPM | Accuracy |
---|---|---|---|
9283 | 2018-06-05 14:16:10 | 75.28 | 98% |