osmosis

passive transport

transport down a concentration gradient where no ATP is needed

water potential

tendency of water molecules to move from one place to another

high water potential

less negative…dilute solution with high water concentration

low water potential

more negative…concentrated solution with low water concentration

partially permeable membrane

membrane providing a barrier for most substances

osmosis

net movement of water molecules from an area of high water potential to an area low water potential through a partially permeable membrane

solution

solute dissolved in a solvent

water potential measurement

in negative values…0 being the highest potential for distilled water

animal cells in dilute solutions

water moves into cells by osmosis…cells swell and burst

animal cells in concentrated solutions

water moves out of cells by osmosis…cells shrivel/shrink

turgidity

water enters the cell by osmosis…organelles push up against the cell wall causing the cell to become rigid

plasmolysis

water exits the cell by osmosis…organelles move towards the centre of the cell causing the cell to become flaccid

incipient plasmolysis

point at which pressure has just reached zero and plasmolysis is about to occur