A new topic was introduced to the class. The icebreaker used was a lab based on the topic. This was the lab that was carried out.
Required materials
- Beaker or transparent glass / plastic bowl
- Thistle funnel – a transparent glass funnel with a long, calibrated tube
- Concentrated sugar solution
- Distilled water
- Semi permeable membrane such as parchment paper or cellophane
- Twine to secure the membrane to the mouth of the Thistle funnel
- Stand with a clamp to hold the Thistle funnel in position
Estimated Experiment Time
Approximately 10 minutes to set up the apparatus and 2-3 hours thereafter to make the observations.
Step-By-Step Procedure
- 1. Fit a semi-permeable membrane carefully over the mouth of a thistle-funnel with the help of strong twine.
- 2. Invert the funnel so that the covered mouth is at the bottom and fill the cup of the funnel with concentrated sugar solution.
- 3. Fill the beaker with distilled water and then immerse the funnel containing the concentrated sugar solution into it with the membrane-covered portion towards the base of the beaker.
- 4. Clamp the tube of the thistle-funnel in a vertical position leaving a gap between its covered mouth and the base of the beaker.
- 5. Mark the level of sugar solution in the tube of the Thistle funnel and leave for some time.
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Afterwards the Topic Osmosis was introduced.
What is Osmosis?
Osmosis is the movement of water molecules from a region of higher concentration to a region of lower concentration via a selective or semi permeable membrane ( the cell membrane has some control over what can cross it, so that only certain molecules either enter or leave the cell.).
How does osmosis work in a cell?
Via The cell membrane which acts as a barrier it determines what enters and leaves the cell.
If you still don't understand watch this video
http://www.youtube.com/watch?v=CIDN-jk5k6I
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Diagram showing osmosis in a potato cell.
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After osmosis changes in a call may be noticed. The cell may become turgid or flaccid.
Turgid Cell: The cell has taken in maximum water in its vacuole and now appears swollen.
Flaccid: All liquid leaves the cell causing the cytoplasm to shrivel up and detach from the cell wall and cell membrane
Thats All For Now
Hope you liked science today.
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