osmosis

    Cards (7)

    • osmosis refers to the movement of which molecules
      water molecules
    • what is osmosis
      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
      1. there will be a higher water concentration (water potential) within the plant cell than in the salty solution surrounding it
      2. so water will move from the inside of the plant cell to the outside, by osmosis
      3. this will cause the cell to shrink and become plasmolysed
    • what happens if you place a plant cell in a beaker of pure water
      1. there will be a lower water concentration (water concentration) within the plant cell than in the pure water surrounding it
      2. so water will move from the beaker into the plant cell, by osmosis
      3. 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