1. Mitosis Mix up activity
WATCH THIS FIRST:
Chi Square video link

2. Normal untreated Onion root tip

3. Now let’s look at a different case

4. You should have done this yesterday
Complete the mitotic mix up activity chart portion for both tissue samples
Now we know what the normal percentage of time a ORT cell spends in each stage of mitosis
We should have a percentage of cells in each stage for the caffeine treated and the untreated cells

5. 1/12:Step by step
Label a page in your lab notebook: the effects of caffeine mitosis.
Do you think caffeine will effect the rate of mitosis?
Let’s go with the null hypothesis.
Write the null hypothesis for this experiment in your notebook.
Make sure you watched the video linked in the first slide of this power point here it is again:

6. Observed Versus Expected
Working from H0= Caffeine does not effect the rate of mitosis in the root tip of onion plants.
Expected would be the normal rates(percentages) of each stage of the cell cycle
Observed would be the percentages of cells in each stage of the cell cycle after caffeine treatment

7. Chi Square Chart
Indicate what you are counting in your notebook. Describe your brief procedure : briefly describe how you decided a cell was in each stage
Create the chart below and fill it in
Stage
# observed (O)
# expected (E)
(O-E)
(O-E)2
(O-E)2/E
Inter
Pro
Meta
Ana
Telo
X2=

8. Make a conclusion
Determine the degrees of freedom ( you have 5 groups of data because there are 5 stages)
Use a critical value of .05
Write a paragraph telling if you supported or rejected your null hypothesis and why.
Insert your mitosis mix up completed
Turn this in for a major grade ( you may turn in on Wednesday) If there are questions me

9. Chi Square chart