Procedure: Go to this website and follow these steps. http://www.glencoe.com/sites/common_assets/science/virtual_labs/LS03/LS03.html
- Select one of the three cells pictures at the top of the screen and drag it into one of the beakers.
- Observe the process of osmosis. Determine whether water represented by animated blue arrows, moves into, stays in equilibrium, or moves out of the cell. Observe what happens to the shape and size of the cell.
- Record your observations in the table below.
- Move the cell to a different beaker or choose a different cell. Observe the process of osmosis again and record your observations in the table.
- Repeat this activity with all three cells and all three solutions.
- Answer the 5 conclusion questions below
Complete the table
Molecule
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Red Blood Cell: Net water Movement In/Out
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Red Blood Cell: Appearance of Cell
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Elodea: Net water Movement In /Out
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Elodea: Appearance of Cell
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Paramecium: Net water Movement In /Out
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Paramecium: Appearance of Cell
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Hypotonic
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Isotonic
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Hypertonic
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Answer the questions:
- Did water move into the cell or out of the cell while it was surrounded by hypotonic solution? Explain your answer.
- In which direction did the water move through the cell membrane when the cell was surrounded by the hypertonic solution? Explain your answer
- Could Elodea or Paramecium from a freshwater lake be expected to survive if transplanted into the ocean? Explain your answer.
- For a science perspective is it better to put salt on a meat dish before or after you cook it? Provide an explanation for your answer. Hint use osmosis.
- Have you ever noticed that salad looks soggy if you add dressing and then leave it in the refrigerator overnight? Explain why this happens in terms of osmosis.