1. Selectively Permeable Membranes “Lab” Honors Biology

2. Pre-lab Before you begin the lab, it is important that you answer the 5 pre- lab questions. Use the next few slides (or your notes or the book) if you do not already know the answers to these questions!

3. Did you know? Isotonic solutions have the same amount of solute as a cell

4. Did you know? Hypertonic Solutions have more solute than a cell

5. Did you know? Hypotonic solutions have less solute than a cell

6. Still confused? Here is a great animation of hypertonic/hypertonic cells: http://www.zerobio.com/flashmx/tonicity.swf http://www.zerobio.com/flashmx/tonicity.swf Here are pictures of actual cells in all 3 solutions: http://highered.mcgraw- hill.com/sites/0072495855/student_view0/chapter21/ animation__hemolysis_and_crenation.html

7. Part I Plant Root Tissues in Solution

8. Plant Tissue in Solution 15% Salt Solution 5% Salt Solution Distilled Water

9. Part II Plant Leaf Cells in Solution

10. Initial Image Salt Water Solution Distilled Water

11. Want to see another image for Part II? Here is a link to a YouTube video that will help you see what happens to a cell placed in a salt water solution: http://www.youtube.com/watch?v=lzDlGl3b4is&fe ature=related http://www.youtube.com/watch?v=lzDlGl3b4is&fe ature=related This is an onion cell, so you will not see chloroplasts, but it will really help you see the change in size of the cell! Remember that the cell wall will not change size, just the cell membrane.

12. Part III Simulated Animal Cells in Solution

13. Benedict’s Test After 24 Hours Iodine Test After 24 Hours Initial Set-Up

14. Post-Lab Now answer the 5 post-lab questions. If you have any questions please see your teacher! You will be designing your own lab investigations in the coming week and all of the information from this lab will be important to understand!