Exercise 8: The Plasma Mem
ane NAME:______________________
Skill Check Worksheet LAB SECTION_________________
Pre-Lab Video Exercise
Cell Homeostasis Virtual La
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
Dialysis Tube Weights (Grams)
A
B
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 mem
anes.
Color of glucose/starch solution in dialysis bag at start of experiment no color-clea
Color of solution in beaker at start of experiment golden 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
Original Contents
Original Colo
Final Colo
Glucose Present? (dipstick results)
Bag
Glucose and starch
clea
Dark Brown
lack
Positive for glucose
Beake
I2KI and wate
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 Mem
ane of Red Blood Cells
DI
0.45
0.90
1.50
2.00
Undiluted
Opacity Reading
clea
clea
Slightly cloudy
Slightly cloudy
Slightly cloudy
opaque
Description of Cells
No cells visible
No cells visible
Swollen Balloon shaped cells
Star-shaped cells
Star-shaped cells
Biconcave cells
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 occu
ed with the cells in the tubes?
Activity 3: Inherited Mem
ane 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 ma
y?
· 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 ma
y?
· 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:
C. Cystic Fi
osis
Should the couple:
· Decide not to ma
y?
· 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: