A student investigated the diffusion of dissolved substance M into cells. The temperature and total membrane surface area were the same in both conditions.
| Condition | Concentration of M outside the cells (mg/dm³) | Concentration of M inside the cells (mg/dm³) |
|---|---|---|
| A | 18 | 9 |
| B | 12 | 1 |
Calculate the concentration difference for condition A and for condition B.
Use your answers to part (a) to predict which condition would have the faster rate of net diffusion of M into the cells. Give a reason for your answer.
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.