Plant cells are grown in a nutrient solution. Their cell membranes are partially permeable.
The table shows the concentrations and the net movement of three substances at the start of an investigation.
| Movement observed | Concentration measured | Outside the cells | Inside the cells |
|---|---|---|---|
| oxygen moves into the cells | oxygen (mmol/dm³) | 0.24 | 0.05 |
| water moves into the cells | total dissolved substances (mol/dm³) | 0.20 | 0.30 |
| magnesium ions move into the cells | magnesium ions (mmol/dm³) | 0.05 | 1.20 |
A scientist adds a substance that prevents the cells releasing energy by respiration. During the next minute, the substance does not damage the cell membranes and the concentrations remain as shown in the table.
Compare the processes responsible for the three observed movements.
Your answer should use the concentration data and include the effect of preventing energy release by respiration on each movement.
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.