A single-celled alga lives in fresh water. The alga has a partially permeable cell membrane.
The cell contents are more concentrated than the fresh water around the alga.
The table shows information about two substances moving into the alga.
| Substance | Concentration outside the cell | Concentration inside the cell | Observed movement |
|---|---|---|---|
| oxygen | higher | lower | into the cell |
| nitrate ions | lower | higher | into the cell |
Name the process by which oxygen moves into the cell.
State the direction in which water moves across the cell membrane.
Name the process by which the water moves.
Explain how nitrate ions can continue to enter the cell.
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.