Observational Design Diagram

1. Observational Design Diagram Title: Observable Structures in Plant and Animal Cells Hypothesis: If plant and animal cells are viewed under a compound microscope, the observable differences will be….. Independent Variable: Type of Cell Dependent Variables: Shape, Arrangement, Size, Structures

2. Materials Needed: 1. Microscope 5. Elodea leaf 9. Salt Water 2. Microscope Slides 6. Toothpick 10. Dropper 3. Cover Slips 7. Iodine 4. Onion 8. Water Procedure Outline: 1. Break a piece of onion and spread the epidermis on the slide. 2. Add a drop of water to the onion. 3. Add a drop of iodine to the water. 4. Place a cover slip over the onion cells. 5. Place a drop of salt water on a new slide. 6. Gently scrape the inside of your cheek with a toothpick. 7.Gently stir the cheek cells off of the toothpick into the drop of water on the slide. 8. Place a drop of iodine on the cheek cells. 9. Place a cover slip over the cheek cells. 10. Place an elodea leaf on a new slide. 11. Add a drop of water to the slide. 12. Place a cover slip over the elodea cells. 13. Observe all three types of cells and create a data table displaying your findings. 14. Add a drop of salt water to the edge of the cover slip on the elodea slide and pull it across the specimen using a bit of paper towel on the opposite edge. Observe the cell membrane. 15. Type a lab report.

3. Conclusion: • Summarize the data from your table. • Explain why you think plant and animal cells have evolved different structures. • Explain some way that this data could be useful to someone? • What could we have done to improve on this activity?