Lab 15: Population Genetics - eScience Labs

Lab 7: Osmosis
5. Osmosis is how excess salts that accumulate in cells are transferred to the blood stream so
they can be removed from the body. Explain how you think this process works in terms of
tonicity.
Experiment 2: Tonicity and the plant cell
Plant cells are able to generate osmotic pressure while other cells cannot. This is due to specialized
plant structures such as the cell wall which prevent lysis caused by osmosis. By taking advantage of this
system, you will be able to look at the effects of tonicity in a biological system.
Materials
20% Sodium chloride (NaCl) solution
Several types of potatoes (e.g. russet,
Yukon, yams)*
2 Plastic test tubes
100mL Graduated cylinder
Water*
2 Pipettes
Knife for cutting*
Ruler
Paper towel*
Watch*
Permanent marker
*You must provide
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