The table shows concentrations of substance X inside and outside four cells. X can cross their membranes by diffusion. Cell size, membrane permeability and temperature are the same.
Table
| Cell | Concentration inside / arbitrary units | Concentration outside / arbitrary units |
|---|---|---|
| P | 2 | 5 |
| Q | 8 | 10 |
| R | 6 | 2 |
| S | 1 | 6 |
Which cell has the greatest initial net rate of diffusion of X into it?
cell P
cell Q
cell R
cell S
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.