A scientist grew animal cells in a nutrient solution containing substance X.
During an 18-minute period, a sample of the cells took up 72 µg of substance X.
The table shows the concentration of substance X at the end of the 18-minute period.
| Location | Concentration of substance X in mmol per dm3\text{dm}^3dm3 |
|---|---|
| Nutrient solution outside the cells | 0.30 |
| Inside the cells | 1.20 |
Calculate how much substance X the sample of cells took up in 1 minute.
Calculate the ratio of the concentration inside the cells to the concentration outside the cells.
Give your answer in the form x:1x : 1x:1.
At the end of the investigation, the cells were still taking up substance X.
Give the name of the transport process responsible for this uptake.
Give the source of the energy used by this transport process.
Give the sub-cellular structure likely to be present in large numbers in cells with a high rate of uptake of substance X.
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.