A student records the mass of a potato cylinder in a large volume of sugar solution. Only water crosses the cell membranes.
Table
| Time / minutes | Mass / g |
|---|---|
| 0 | 5.00 |
| 10 | 4.70 |
| 20 | 4.50 |
| 30 | 4.40 |
| 40 | 4.40 |
Which statement best explains the pattern?
water enters by osmosis, and its concentration gradient increases
sugar leaves by diffusion, and all sugar movement eventually stops
water leaves by active transport, and the cells eventually use all their energy
water leaves by osmosis, and net water movement eventually becomes zero
41 exam-style questions on Edexcel GCSE Biology 1.4 Transport across cell membranes, covering 1.4.1 Transport into and out of cells and 1.4.2 Percentage gain and loss in osmosis. Each one has a worked solution and a mark scheme showing where the marks go.