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Homeostasis & Transport |
Section 5-1 Passive Transport
1. What is the purpose of the cell membrane?
2. Explain passive transport.
3. What is the simplest type of passive transport?
4. In which direction does diffusion occur?
5. What is a concentration gradient?
6. Sugar dissolving in water is an example of _______________________.
7. What supplies the energy for diffusion?
8. Molecules are constantly _____________________.
9. What is meant by equilibrium?
10. Do molecules stop moving when equilibrium is reached? Explain.
11. List three things that determine if a molecule will be able to diffuse across a membrane.
12. Name the 2 parts of a solution.
13. Define osmosis. Is it passive or active transport?
14. The direction water moves across a cell membrane depends on the concentration of what on either side of the cell membrane?
15. Explain what is true about solutes if the outside of the cell is hypotonic to the cytosol? Which way does water move?
16. Explain the solute conditions if the outside is hypertonic to the cytosol. Which way does water move?
17. What occurs if the solute concentration on each side of the cell membrane is isotonic?
18. If the inside & outside of a cell are both isotonic, does water still move across the cell membrane? Explain.
19. If the inside of the cell is hypotonic, the outside will be _________________________.
20. Water tends to diffuse from ____________________ to ___________________ solutions.
21. How does a unicellular paramecium get rid of its excess water? Is energy used?
22. Many cells in multicellular organisms have _________________ pumps to prevent them from taking in too much water in hypotonic solutions.
23. What structure around the outside of plant cells keeps hem from rupturing from too much water?
24. What is turgor pressure & how does it help plant cells?
25. What happens to plant cells placed in a hypertonic solution? Name this process.
26. What is cytolysis & what causes it?
27. Another type of passive transport is __________________________ diffusion.
28. Explain how carrier proteins help in facilitated.
29. Sketch the changes that take place in a carrier protein as it helps molecules move across the cell membrane.
30. What sugar moves across the cell membrane by facilitated diffusion?
31. What are ion channels & are they used in passive or active transport?
32. Name 4 ions that cross the cell membrane through ion channels.
33. Why can’t these ions diffuse across the lipid bilayer of the cell membrane?
34. Ion channels may be always ________________ or have ___________________.
35. Name 3 stimuli that open & close gated channels.
Section 5-2 Active Transport
36. Define active transport.
37. Why are carrier proteins in the cell membrane that are used for active transport called “pumps”?
38. What is the best-known carrier protein pump in animal cells?
39. What 2 ions move up their concentration gradient in this pump?
40. ___________________ ions are pumped out, while ______________ ions are pumped into the cell.
41. Is energy required for active transport? Explain.
42. Sodium ions are exchanged for potassium ions at a ____________ to ____________ ratio.
43. Name 2 processes used to move macromolecules & food particles across the cell membrane. Is energy required?
44. Explain how cells move large particles into the cell by endocytosis.
45. Name & describe the 2 types of endocytosis.
46. How do phagocytes protect cells?
47. What process moves large materials such as wastes & proteins out of the cell?


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Homer notices that his shower is covered in a strange green slime. His friend Barney tells him that coconut juice will get rid of the green slime. Homer decides to check this out by spraying half of the shower with coconut juice. He sprays the other half of the shower with water. After 3 days of “treatment” there is no change in the appearance of the green slime on either side of the shower.
he’s been reading too much Radioactive Man). He decides to perform this experiment by placing 10 mice in a microwave for 10 seconds. He compared these 10 mice to another 10 mice that had not been exposed. His test consisted of a heavy block of wood that blocked the mouse food. he found that 8 out of 10 of the micro waved mice were able to push the block away. 7 out of 10 of the non-micro waved mice were able to do the same.
Krusty was told that a certain itching powder was the newest best thing on the market, it even claims to cause 50% longer lasting itches. Interested in this product, he buys the itching powder and compares it to his usual product. One test subject (A) is sprinkled with the original itching powder, and another test subject (B) was sprinkled with the Experimental itching powder. Subject A reported having itches for 30 minutes. Subject B reported to have itches for 45 minutes.