A cell from the lining of the mouth is placed in a solution containing water and dissolved substances. After 10 minutes, the volume of the cell has not changed.
Which statement explains why the volume of the cell has not changed?
The cell and the solution are equally concentrated, so there is no net movement of water.
The cell membrane lets the dissolved substances through but blocks the water molecules.
Water molecules stop moving when the cell reaches a stable volume.
The cell uses energy from respiration to pump water out as fast as it enters.
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.