Two flexible chambers, X and Y, each contain 50 cm³ of the same concentrated sugar solution. Each chamber has a window made from the same partially permeable membrane. The remaining walls are impermeable. The membrane window of X has an area of 40 cm² and the membrane window of Y has an area of 20 cm². Both chambers are placed in the same dilute sugar solution at the same temperature. Both chambers eventually take in more than 3 cm³ of water. Which statement about the time taken to take in 3 cm³ of water is correct?
X and Y take the same time, because both chambers contain the same volume of sugar solution.
X takes less time, because its larger membrane window allows more water molecules to cross at the same time.
X takes less time, because its larger membrane window increases the concentration of the sugar solution inside X.
Y takes less time, because its smaller membrane window produces a steeper concentration gradient for water.
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.