A student takes two epidermal strips from a red onion (Allium cepa) bulb. She places one strip in a 0.1 mol/dm30.1\text{ mol/dm}^30.1 mol/dm3 sodium chloride solution and the second strip in a 1.0 mol/dm31.0\text{ mol/dm}^31.0 mol/dm3 sodium chloride solution. She then uses a light microscope to photograph the cells in each treatment as shown in the diagram:
Suggest why red onion epidermal cells are particularly useful when carrying out this investigation.
Explain what is meant by the term osmosis.
Explain why the red onion cells in 1.0 mol/dm31.0\text{ mol/dm}^31.0 mol/dm3 sodium chloride solution look different from those placed in 0.1 mol/dm30.1\text{ mol/dm}^30.1 mol/dm3 sodium chloride solution.
When human red blood cells are placed in distilled water, they swell and burst, meaning no intact cells can be seen under the microscope. Explain why this happens to red blood cells, but does not happen to the red onion epidermal cells.