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The purpose of the activities is to help you review material you have already studied in class or have read in your text. Some of the material will extend your knowledge beyond your classwork or textbook reading. At the end of each activity, you can assess your progress through a Self-Quiz.
To begin, click on an activity title.
Lab 2 Enzyme Catalysis
Mitosis and Meiosis
Plant Pigments and Photosynthesis
6-I Bacterial Transformation
6-II DNA Electrophoresis
Genetics of Organisms
Population Genetics and Evolution
10-I Cardiovascular Fitness
10-II Heart Rate in Daphnia
Biomembranes I: Membrane Structure and Transport
Biomembranes II: Membrane Dynamics and Communication
Cardiovascular System I: The Beating Heart
Cardiovascular System II: The Vascular Highway
Cell Structure and Function
DNA Structure and Replication
From Gene to Protein: Transcription
From Gene to Protein: Translation (Protein Synthesis)
Plant Structure and Growth
Properties of Biomolecules
Restriction Enzyme Digestion of DNA
The lac Operon in E. coli
Analysis of Results
So that you might better understand the procedure for calculating water potential, here is a practice problem.
Once you know the solute concentration, you can calculate solute potential using the following formula:
Solute potential (Ψs) = −iCRT
i = The number of particles the molecule will make in water; for NaCl this would be 2; for sucrose or glucose, this number is 1
C = Molar concentration (from your experimental data)
R = Pressure constant = 0.0831 liter bar/mole K
T = Temperature in degrees Kelvin = 273 + °C of solution
The molar concentration of a sugar solution in an open beaker has been determined to be 0.3M. Calculate the solute potential at 27 degrees. Round your answer to the nearest hundredth.
The pressure potential of a solution open to the air is zero. Since you know the solute potential of the solution, you can now calculate the water potential. (If you need to, review the equation for calculating water potential.)
What is the water potential for this example? Round your answer to the nearest hundredth.