Download CellMembraneWebQuest2012-2013(Honors)

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Homeostasis and Cell Transport WebQuest
Objectives: Understand the structure and function of the cell membrane. Understand how cells and single–celled
organisms maintain homeostasis using cell transport mechanisms.
Part I: The Cell Membrane & Introduction to Transport
Use the link below to answer questions 1-16.
http://www.ibiblio.org/virtualcell/textbook/chapter3/cm.htm
1. What are the two different structures that make up the cell membrane?
2. Which of these structures has a tail?
3. How many “parts” are there to a phospholipid? Describe each of these parts being sure to note which part “loves”
water and which one “fears” water. What scientific terms are used for these two characteristics?
4. What happens if you mix phospholipids in water? Why
5. What “floats” around in the membrane? What are the three categories of these materials?
6. What steroid is sometimes found in a cell membrane? What is its job?
7. What are the three general functions of a cell membrane?
8. What are two types of transport proteins? Describe what they do.
9. What is it called when molecules randomly move through a cell membrane? Does this process require energy? In
what “direction” to these molecules move?
10. What are symports?
11. When energy is required to transport materials into or out of a cell, what chemical in the body does this energy
usually come from?
12. What are marker proteins? What human system uses them?
13. What proteins are used for intercellular communication?
14. What is endocytosis?
15. What is exocytosis?
16. Please draw a diagram below that can depict the process of both endo and exocytosis.
Part II: Passive Transport
Use the link below to answer questions 1 & 2.
http://physioweb.med.uvm.edu/diffusion
1. Draw an outline of a cell. Show the internal and external concentrations of water on the inside and the outside of
the cell that would cause a concentration gradient.
2. Define the term diffusion.
Use the link below to answer questions 1-10.
http://programs.northlandcollege.edu/biology/Biology1111/animations/transport1.html
1. The movement of substances across a cell membrane without any energy expenditure by the cell is ______________
_______________.
2. What are the three types of passive transport?
a.
b.
c.
3. What is the function of an integral protein?
4. _____________ molecules do NOT pass through the cell membrane easily, while _____________ molecules pass
through the membrane easily.
5. Define the term concentration gradient:
6. List four factors that affect the rate of diffusion
a.
b.
c.
d.
7. Facilitated diffusion would be used on large molecules (True or False).
8. Facilitated diffusion requires the use of special membrane proteins. (True or False).
9. Define osmosis:
10. a. Draw a cell.
b. Label the interior of the cell as 90% H2O and 10% solute. Label the exterior of the cell as 100% H2O. Does a
concentration gradient exist? (Y/N) _________
c. Label the exterior and interior of the cell using the terms hypertonic and hypotonic.
d. According to osmosis, which way would water move in this cell’s environment?
Part III: Active Transport
Use the link below to answer questions 1-6.
http://programs.northlandcollege.edu/biology/Biology1111/animations/transport1.html
1. The movement of substances across a cell membrane requiring energy expenditure by the cell is
______________ _______________.
2. In an ion pump, what kind of concentration gradient is established? _______________________
3. In an ion pump, what molecule is used to supply the energy required to move molecules (such as the H+ ions shown) up
the concentration gradient? ______________
4. Some cells are able to infold their cell membranes to literally engulf substances. This general process is called
_______________ and (does/does not) ____________ require energy.
5. List the three types of endocytosis.
a.
b.
c.
6. Name one organism that would use phagocytosis.
a.
7. What does the term exocytosis might mean?
Use the link below to answer questions 1-3.
http://www.susanahalpine.com/anim/Life/endo.htm
1. What is the role of the receptor proteins on the surface of the cell membrane?
2. What eventually happens to the receptor proteins?
3. What is the role of the lysosome in the animation/process?
Part IV: Blood Cells
Use the links below to answer questions 1-3.
Isotonic Solution: http://www.biosci.ohiou.edu/introbioslab/Bios170/170_3/iso.htm
Hypertonic Solution: http://www.biosci.ohiou.edu/introbioslab/Bios170/170_3/hyper.htm
Hypotonic Solution: http://www.biosci.ohiou.edu/introbioslab/Bios170/170_3/hypo.htm
1. Draw a red blood cell in an isotonic solution. Use 90% water and 10% solute as the
concentration inside the cell. Label the external environment of the cell appropriately.
2. Draw a red blood cell in a hypertonic solution. Use 90% water and 10% solute as the
concentration inside the cell. Label the external environment of the cell appropriately.
3. Draw a red blood cell in a hypotonic solution. Use 90% water and 10% solute as the
concentration inside the cell. Label the external environment of the cell appropriately.