A specific form of diffusion which involves the movement of water molecules from a high concentratio

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OSMOSIS

• A specific form of diffusion which involves the
  movement of water molecules from a high
  concentration to a low concentration through a
  selectively permeable membrane.

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Why is osmosis so important?

• All life needs water
• From singled celled organisms, to multi-cellular
  organisms such as plants and mammals.
• But, we need just the right concentration of
  water. Too much or too little and the cells
  wont work properly.

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Which of the following is correct?
Hypotonic
hypertonic
or
hypotonic
hypertonic
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water always moves from a hypotonic to a
hypertonic solution.
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So what happens when red cells are hypotonic to
their surroundings?
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The cells lose water and shrivel up.
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So what happens when red cells are hypertonic to
their surroundings?
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The cell swells up and can burst.
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The cell swells up and can burst.
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The cell swells up and can burst.
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The cell swells up and can burst.
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Hypotonic inside red blood cell
Water is lost to surroundings and cells shrink
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Hypertonic inside red blood cell
Water is taken up by the cell and the cell swells
up
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Isotonic inside red blood cell
No change, concentration of water outside is the
same as inside.
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Place plant cell in a hypotonic solution (higher
water concentration on the outside).
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The cell has become fully turgid
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Place plant cell in a hypertonic solution (lower
water concentration on outside)
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The cell has become plasmolysed
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Correct
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Wrong Try Again
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AGAIN
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Wrong Try Again
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