Purpose- This assignment ties together the concepts of simultaneous diffusion and osmosis.
Instructions
Required resources: the information in the textbook chapter and associated lecture highlights.
Complete the worksheet document.
Chapter 7 Assignment Simultaneous Diffusion and Osmosis-6.docxDownload Chapter 7 Assignment Simultaneous Diffusion and Osmosis-6.docx
Attempts are unlimited until the due date.
Review the grading rubric.
Suggestions:
Word in Office 365 has a drawing tab. Use a stylus (digital pen) so that your work is legible. Another option: You can also upload the file to Windows whiteboard and write on the document there. Typing in a textbox is another option.
If you choose to print out the file, photograph each page and convert it to a pdf. There are many apps available to do the task. Also, make sure the initial photo is sized and positioned correctly. It must be legible.
Hoffman
Biology 1406 Lecture
Chapter 7
Simultaneous Diffusion and Osmosis
Building Knowledge
Hover the mouse over the embedded video. Select play and YouTube. Pause it to take notes. Then, read about the topic in the textbook chapter. While watching the video, pay close attention to the percentages of solutes and solvent on either side of the artificial membrane. Note how the concentration gradient of the solute and solvent affects the overall direction of the movement of free water. Be aware that the total percentage of solvent + solute on each side of the membrane equals 100%.
1. From the information in the textbook chapter and lecture highlight, define free water. Define a concentration gradient. Then, define osmosis.
Hoffman
Biology 1406 Lecture
2. Use the information in the textbook and figure 7.11 to explain the diffusion of one and then two different solutes across a semipermeable membrane. Does the diffusion of one type of solute affect the diffusion of another type of solute? Explain in no more than six sentences.
3. From the video, define tonicity. From the information in the textbook chapter and lecture highlight, define isotonic, hypertonic, and hypotonic solutions. No more than six sentences.
Hoffman
Biology 1406 Lecture
Application
Review the notes taken while watching the video. Then, read in the textbook chapter and figure 7.12 about the U-shaped glass tube experiment. Understand why at the end of the experiment the solution concentrations on either side of the artificial membrane are the same, but the volumes are not.
Next
Use the illustration below to answer the following statements. Write on it to assist your learning. Rather than percentages, molar concentrations of solutes are given. Glucose is not permeable across the artificial membrane. Salt is permeable across the artificial membrane.
1. In reference to the initial setup, which side has a higher free water concentration? Which side is hypertonic to the other side? Explain why in no more than two sentences.
Hoffman
Biology 1406 Lecture
2. Draw the U-shaped tube. Label side A and B. Draw the approximate volume levels on each side of the membrane, once the experiment reaches equilibrium (after the initial setup). In terms of a concentration gradient, explain how the movement of free water affected the result. In terms of concentration gradients, explain how the movement or nonmovement of each kind of solute affected the result. No more than six sentences.
3. In reference to the end of the experiment, explain why the solution concentrations are approximately the same on each side of the membrane. In other words, explain why the solutions on either side of the membrane are isotonic to each other. No more than six sentences.
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