This experiment showed how potato discs placed in concentrated sucrose solution overnight lost mass, due to the movement of water out of the tissue into the surrounding environment. The potato in distilled water gained mass, due to the movement of water from the environment into the cells. This diffusion of water through a semi-permeable membrane (the plasma membrane) is called ‘osmosis’. Learn about the three forms of passive transport (diffusion, facilitated diffusion and osmosis) and active transport (including ion pumps, cotransport and endocytosis) at this site: Northland College Biology.
Next week we will start Chapter 3 and on Wednesday, do an experiment with cylinders of beetroot. We will be testing the temperature tolerance limits of beetroot cell membranes.