Substances move into and out of cells by diffusion, by osmosis and by active transport.
Compare the three processes.
In your answer you should refer to:
58 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.