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Patterns in Nature . Diffusion and Osmosis. The processes of diffusion and osmosis account for much of the passive movement of molecules at the cellular level. DIFFUSION. OSMOSIS. MOVEMENT OF MOLECULES IN SOLUTION. Concentration gradient.
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Diffusion and Osmosis The processes of diffusion and osmosis account for much of the passive movement of molecules at the cellular level.
Perform a first hand investigation to demonstrate the difference between osmosis and diffusion. Aim: Experiment A: To observe the process of osmosis using a unboiled potato and a boiled potato. Experiment B: To observe the process of diffusion using coloured dye. Materials: Experiment A:Experiment B: Unboiled potato BeakerBoiled potato WaterSpatula Coloured dye Table saltWater 2 Petri dishes
Perform a first hand investigation to demonstrate the difference between osmosis and diffusion. Method: Experiment A:1. Using a spatula make a hole in the middle of the unboiled and boiled potato. Make sure not to reach the base of potato, however still deep. Put aside. 2. Fill the two petri dishes with ¾ of water. 3. Place the unboiled potato and boiled potato in the middle of each petri dish.4. Add half a teaspoon of salt into each hole of the unboiled and boiled potato.5. Leave aside for 10 minutes. Start experiment B.
Perform a first hand investigation to demonstrate the difference between osmosis and diffusion. Method: Experiment B:6. Collect a beaker, fill it with water. Do not overflow.7. Add a few drops of dye into the beaker.8. Observe the beaker for about 3 minutes, note what is happening.9. Once finished with the beaker, observe the rested potato, note any changes.
Types of solutions based on solute concentration In the illustration, the solution in the bag contains less solute than the solution in the beaker. The solution in the bag is hypotonic (lower solute concentration) to the solution in the beaker. The solution in the beaker is hypertonic (higher solute concentration) to the one in the bag. Water will move from the hypotonic solution into the hypertonic solution. In this illustration the two solutions are equal in their solute concentrations. We say that they are isotonic to each other.