1. Onion Root Mitosis

2. Background In plants, the roots grow as they search for water and nutrients. These regions of growth are good for studying the cell cycle because at any given time, you can find cells that are undergoing mitosis. (Interphase is NOT considered a phase of mitosis, however it is part of the cell cycle.)

3. Background Today you will be looking at prepared microscope slides of thin slices of onion root tips. These tips are the part of the root that is constantly growing in order to find nutrients and water.

4. Hypothesis Today you will be looking at 25 onion root cells. Your hypothesis should be a statement as to what percentage of these constantly splitting cells will be in interphase, prophase, metaphase, anaphase and telophase.

5. Materials Microscope Prepared slides of onion root tips Data sheet Colored Pencils

6. Where To Look

7. Prophase

8. Metaphase

9. Anaphase

10. Telophase

11. Data: Table 1 – Totals for Cell Cycle InterphaseProphaseMetaphaseAnaphaseTelophaseTotal Class Tally Class Totals Class Percentage