ap lectureguide08

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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