# Potato Lab Modified (1).pdf - uJ~ f>~bau00b71 u5'7 Lab...

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Exercise 2: Water Potential 'I' uJ~ f>~ba·1 Lab u5'7 f:>o-fa,fo r!.,t;/l'S In this exercise, you will use potato cores placed in different molar concentrations of sucrose in order to determine the water potential of the potato cells. Water potential is a concept used to predict the movement of water into and out of a plant cell. Water potential is the potential for water to move from one area in favor of another. Therefore, water will always move from an area of higher water potential to an area of lower water potential. Water potential is affected by two physical factors. One factor is the addition of solute which lowers water potential. The other factor is physical pressure, which increases water potential. Therefore, water we can calculate water potential as the sum of pressure potential and solute potential. Water potential (\jf) = Pressure potential + Solute potential By convention, the water potential of distilled water at standard atmospheric pressure is O. Solute potential is the relative concentration of a solute. A solution exposed to atmospheric pressure is said to have a pressure potential of zero. Solute potential of distilled water is always 0 and the solute potential of a solution is always going to be less than zero. Therefore, a solution with a solute potential of -5 has a greater concentration of solutes than a solution with solute potential of -3. On the other hand, as water moves into a cell, the pressure potential will increase. If a cell with solute potential -3 is placed in distilled water (water potential of 0),
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