AP Biology: CHAPTER 8
Cell Membranes
1. What evidence supports the fluid mosaic model of the cell membrane? __________________
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2. What is meant by membrane fluidity? ____________________________________________
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3. How is fluidity reduced in animal cells? ___________________________________________
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4. Describe the orientation of the membrane proteins
a. Peripheral _______________________________________________________________
b. Integral _________________________________________________________________
5. How are the two sides of the membrane different? __________________________________
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6. List and briefly define the roles of the membrane proteins.
a. _______________________________________________________________________
b. _______________________________________________________________________
c. _______________________________________________________________________
d. _______________________________________________________________________
e. _______________________________________________________________________
f. _______________________________________________________________________
7. What membrane structures are important for cell-cell recognition? ______________________
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8. Which molecules easily cross the membrane? _____________________________________
9. How are molecules transported that do not easily cross the membrane? _________________
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10. Define the following:
a. Diffusion ________________________________________________________________
b. Osmosis ________________________________________________________________
c. Hypotonic _______________________________________________________________
d. Hypertonic ______________________________________________________________
e. Isotonic _________________________________________________________________
11. What is happening in the diagram below?
12. What do cells do when placed in solutions that are:
a. Hypotonic _______________________________________________________________
b. Hypertonic ______________________________________________________________
c. Isotonic _________________________________________________________________
13. How does the Paramecium maintain osmoregulation? _______________________________
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14. What is meant by facilitated diffusion? __________________________________________________________________________
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15. How do active and passive transport differ? ________________________________________
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16. The sodium-potassium pump uses __________________ to pump __________________
out of the cell and _______________ into the cell.
17. How does the membrane generate voltage? _______________________________________
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18. What can the cell do with the voltage generated in the membrane? _____________________
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19. Define co-transport and give an example. __________________________________________
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20. What is the difference between exocytosis and endocytosis? __________________________
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21. Describe an example of receptor-mediated endocytosis. _____________________________
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