Answers to AQA GCSE Osmosis potato mass practical(Biology)
Practice Question
1.What is the purpose of the cork borer?
Cut out uniform cylinders of plant tissue (e.g., potato, beetroot, carrot, etc.)
This ensures that all the samples have the same diameter and shape, so the only variable affecting osmosis is the concentration of the solution, not the size or surface area of the tissue.
2. State the formula for percentage change
3. Using a percentage change in mass vs concentration graph. Explain how we can estimate the concentration of the potato cells.
So, to estimate the concentration of the potato cells:
Draw the graph of % change in mass vs concentration.
Find the point where the line crosses the x-axis (0% change in mass).
The x-coordinate at this point gives the concentration of solutes inside the potato cells.