Turgidity and Support

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Turgidity and Support

• Turgid cells give support keep the stems upright

• Plant cells that lose water wilt

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Turgidity
What happens when a cell is full of water ?
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Turgidity How does it happen?

• Plant cell placed in water, water enters the
  plant cell
• Cell sap contains the stronger solution, water
  passes into the cell by osmosis
• As water enters the cell, the cell swells up, the
  water pushes against the cell wall
• Eventually the cell contains as much water as it
  can hold like a blown up balloon
• The cell wall prevents the cell bursting the
  cell is referred to as being turgid

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Plasmolysis
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Plasmolysis

• Water passes out of the plant cell when it is
  placed in a stronger solution
• As water passes out the sap the vacuole shrinks
• The cells are no longer turgid but flaccid
• As more water leaves the cells the cytoplasm
  starts to peel away from the cell, these cells
  are referred to as being plasmolysed

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Plasmolysis

• When an animal cell is placed in distilled water,
  water passes by osmosis into the cell (cytoplasm
  is the stronger solution)
• There is no cell wall to prevent the cells
  swelling too much so they burst cell lysis

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Osmosis and animal cells
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Summary of Osmosis in plant cells
plasmolysed cell
Turgid cell
flaccid cell