Cell homeostasis virtual lab answer key

Exercise 8: The Plasma Membrane Skill Check Worksheet NAME:______________________ LAB SECTION_________________ Pre-Lab Video Exercise Cell Homeostasis Virtual Lab Answer the following questions based on the Cell Homeostasis Virtual Lab found at https://video.esc4.net/video/assets/Science/Biology/Gateway%20Resources/cell%20homeostasis %20virtual%20lab%20-%20activity/index.html A B Dialysis Tube Weights (Grams) C D E Weight Before Weight after 24 hours Mass difference Now, create a graph that illustrates the relationship between the contents of the tubes and the change in mass experienced over 24 hours. Turn in this graph along with this Skill Check Worksheet. Activity 1: Diffusion of Molecules through Selectively Permeable membranes. Color of glucose/starch solution in dialysis bag at start of experiment Color of solution in beaker at start of experiment golden no color-clear yellow Part A: Pre-Experiment Questions 1. Which molecules do you think will move through the dialysis bag? Why? 2. Which molecules are least likely to move through the dialysis bag? Why? Section A: Relationship between Molecular Size and Diffusion Solution Bag Beaker Original Contents Original Color Final Color Glucose Present? (dipstick results) Glucose and starch clear Dark Brown/black Positive for glucose I2KI and water Golden yellow Golden yellow positive for glucose 1. Describe the results of your tests with reference to the colors of the final solutions. 2. Explain what these results mean in terms of the movement of the various molecules (starch, glucose and I2KI) 3. From your results, predict the size of I2KI molecules relative to the starch and glucose molecules. 4. What results would you have expected if the experiment had started with glucose and I2KI inside the bag and starch in the beaker? Explain why. Activity 2: The Plasma Membrane of Red Blood Cells Opacity Reading DI 0.45 0.90 1.50 2.00 Undiluted clear clear Slightly cloudy Slightly cloudy Slightly cloudy opaque Swollen Balloon shaped cells Starshaped cells Starshaped cells Biconcave cells Description of Cells No cells visible No cells visible Drawing of Cell shape No cells visible No cells visible Were there any differences between the opacity of the undiluted tube when compared with any of the other sample tubes? If there were differences, why were they different? Describe any differences in the microscopic shapes of the cells in each of the tubes compared to the undiluted control. If there were differences, why were there differences? How do the looks of the cells relate to the conditions in the tubes? Were you able to find cells in all of the samples? What is the relationship between the opacity data and the microscopic characteristics of the cells? What does this tell you about what occurred with the cells in the tubes? Activity 3: Inherited Membrane Diseases and the Implications of Genetic Testing For each of the three genetic disease conditions listed below, you along with other members of your group should discuss the pros and cons of each of the listed options. You should attempt to come to a consensus recommendation with the other members of your group and describe the justification. If you did not come to a group consensus, that is ok; write your own recommendation/justification for what the couple should do. Then rank order each of the each of the reasons listed and write a short justification of why you believe what you do. A. Bartter Syndrome Should the couple: • • • • Decide not to marry? Decide not to have children? Conceive a pregnancy and then have the fetus tested, and abort the fetus if it is affected? Decide to keep the offspring from all pregnancies, despite the risk. Recommendation Justification: ❑ ❑ ❑ ❑ ❑ The child’s right to live The child’s anticipated quality of life The potential effects on your family Your responsibility to society Your responsibility to future generations Justification: B. Hereditary Stomatocytosis Should the couple: • • • • Decide not to marry? Decide not to have children? Conceive a pregnancy and then have the fetus tested, and abort the fetus if it is affected? Decide to keep the offspring from all pregnancies, despite the risk.