the net movement of water particles, from an area of higher water concentration, to an area of lower water concentration, across a partially permeable membrane
is osmosis an active or passive process
osmosis is a passive process because it doesn't require any energy from the cell
what is a partially permeable membrane
only some types of molecules can pass through the membrane - other types of molecules can't pass through
what happens if you place a plant cell in a very salty solution
there will be a higher water concentration (water potential) within the plant cell than in the salty solution surrounding it
so water will move from the inside of the plant cell to the outside, by osmosis
this will cause the cell to shrink and become plasmolysed
what happens if you place a plant cell in a beaker of pure water
there will be a lower water concentration (water concentration) within the plant cell than in the pure water surrounding it
so water will move from the beaker into the plant cell, by osmosis
this will cause the cells to expand, and become turgid
when animal cells are placed in pure water they burst, whereas plant cells become turgid. why is this
plant cells have a strong cell wall made of cellulose, which prevents them from bursting