Osmosis

Biology Coursework:
Investigating osmosis in potato cells

AIM: To investigate the affect of changing the concentration of a solution on a potato.

BACKGROUND INFORMATION:

 Osmosis is the diffusion of water from a dilute to a concentrated solution through a selectively permeable membrane, which allows water through but not the solute.
Diagram to show Osmosis

















Information on potato plant cells:
 Turgidity: when plant cells are turgid, the cell looks like this:










When plant cells are placed in water the water enters the cells. This is because their cell sap contains a strong solution. Therefore water passes into the cells by osmosis.

 Plasmolysis:
When plant cells are placed into a stronger sugar or salt solution, water passes out of the cells by osmosis. As water passes out the sap vacuole starts to shrink. These cells are no longer firm, they are limp and we say they are flaccid. As more water l...