Finding examples of osmosis for the biology laboratory that promote student inquiry and offer relatively quick results have been hard to come by. A new osmosis investigation has been developed by Mike Collins, one of our staff biology teachers, that helps students understand this essential concept of cell homeostasis. In this easy to perform experiment, students use their sensory inputs of smell, touch, sight, and possibly taste in combination with software and technology to explore osmosis.
For this experiment, students set up a Vernier interface and a Gas Pressure Sensor to monitor the pressure change in an enclosed cell. Using maple syrup (real maple syrup, not a high fructose imitation) as the intracellular fluid, students can observe qualitatively and quantitatively the effect of water moving regions of higher concentration to those of lesser concentration. Performing several runs of data collection with different concentrations of syrup solution allows students to analyze the relationship between concentration and rates of pressure change.
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