A scientist placed equal samples of bacterial cells into sodium chloride solutions of different concentrations. Each sample was kept at the same temperature for 2 hours.
| Concentration of sodium chloride solution in g/dm³ | Mean cell volume in µm³ | Cells dividing after 2 hours in % |
|---|---|---|
| 0 | 1.20 | 68 |
| 30 | 1.05 | 52 |
| 60 | 0.82 | 21 |
| 90 | 0.61 | 3 |
Explain the results in the table.
Predict how the mean cell volume and the percentage of cells dividing would compare with the results at 90 g/dm³ if the sodium chloride concentration were increased to 120 g/dm³.
140 exam-style questions on AQA GCSE Biology 1.3 Transport in cells, covering 1.3.1 Diffusion, 1.3.2 Osmosis, and 1.3.3 Active transport. Each one has a worked solution and a mark scheme showing where the marks go.