Expert Solutions

1. In terms of diffusion, explain why the substance will begin to leave the bottle?

2. Which area of students should be able to detect the molecules first?

3. Which area of students should be able to detect the molecules last?

4. Describe two circumstances that could cause the particles to distribute unevenly throughout the room?

5. Discuss the effects of all three temperatures, then make a general statement about the effects of temperature on the rate of diffusion.

6. Could starch pass through the membrane?

7. What did you see in the experiment (evidence) that led you to your answer in #6?

8. Could iodine pass through the membrane?

9. What did you see in the experiment (evidence) that led you to your answer in #8?

10. What can you conclude about the general sizes of these two molecules (starch and iodine)?

11. Has water entered or left the cells that are in the salt solution?

12. How did the cell’s physical appearance change in the salt solution?

13. Describe the cell’s appearance after being exposed to pure water?

14. In terms of osmosis and the conditions of the solutions inside and outside the cell, describe why the cells changed as you changed solutions.  In other words, describe what happened during this experiment, using the correct terminology.

15. If you want to make lettuce leaves plump and juicy, would you put them in salt water (hypertonic solution) or tap water (hypotonic solution)?  Explain your answer by correctly using the hypertonic/hypotonic/isotonic concept and terms.