Diffusion in a model cell

Uncover diffusion in a model cell! Learn about molecular movement & membrane permeability.

1. Using a complete sentence describe what happens when iodine comes into contact with starch. 2. Starting Lab Observations Color the lab that is set up to start. Label where the iodine is and where the corn starch is. 3. What is the main difference between osmosis and diffusion? 4. We’re going to think about concentrations now, which substances are more or less concentrated depends on which one has the most stuff in it. Molecules tend to move from areas of high concentration to areas of low concentrations.The high concentration of starch is present in the dialysis tube, while the low concentration of starchis in the beaker. The high concentration of iodine is in the beaker, while the low concentration of iodineis in the dialysis tube. 5. If the dialysis tube was permeable to starch, which way would the starch move, into the tube or out of the tube? into the tube out of the tube 6. If the dialysis tube was permeable to iodine, which way would the iodine move, into the tube or out of the tube? into the tube out of the tube 7. If the dialysis tube was permeable to iodine, what color would you expect the solution in the tube to turn? yellow white purple 8. If the dialysis tube was permeable to starch, what color would you expect the solution in the beaker to turn? yellow white purple 9. Fill in the data table. Data Table Starting Color Color After 20 minutes Solution in the beaker Solution in the tube 10. Based on your observations, which substance moved, the iodine or the starch? How did you determine this? 11. The dialysis tube was permeable to which substance? Explain how you know. 12. Is the dialysis tube selectively permeable? Why or why not? 13. Draw the result of the Lab below. Label where the starch and iodine are. Use arrows to show where the iodine moved.