# Determining the Osmotic Potential

## Determining the Osmotic Potential

• Submitted By: ND2007
• Date Submitted: 02/08/2009 3:35 PM
• Category: Science
• Words: 724
• Page: 3
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The Relationships between Osmosis, Osmotic Potential, Concentration, and Density Introduction Now, the goal of this lab was to find the osmotic potential of the potato cells. Each of the five solutions can either be hypotonic, hypertonic, or isotonic to the potato cell. If a solution is hypotonic, then water will flow into the cells causing the cells to expand and theturgor pressure to increase. When equilibrium is reached in the system, there will have been a net flow of water out of the solution and into the cell ultimately increasing the concentration of the sucrose solution. Based on the assumption that density is an increasing function of concentration, the density of the experimental solution should be greater than the density of the original solution if the original solution is hypotonic. Therefore, if the original solution is hypotonic, the dyed drop of the original solution should rise to the top since it has a lower density. If the original solution is hypertonic, water will flow out of the cell and into the solution which may result in the cell undergoing plasmolysis. (Lab Manual 55) Plasmolysis is when the plasma membrane shrinks away from the cell wall and causes a decrease in pressure potential. (Lab Manual 55) When the system reaches equilibrium, the concentration of the sucrose solution will have decreased since water is being added to the solution. Assuming a decrease in concentration results in a decrease in density, the density of the experimental solution will be less than the density of the original solution if the original solution is hypertonic. Therefore, if the original solution is hypertonic, the dyed drop of the original solution should sink to the bottom since it is denser than the experimental solution. If the original solution is isotonic to the potato cells, then the there will be no net flow of water during osmosis. Remember, isotonic solutions have osmotic potentials equal to thosepotato cells. Since there is no net flow of...