Daphnia Lab
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Purpose:
Hypothesis
Materials:
Procedure:
1. Catch a daphnia from the stock solution using the syringe.
2. Place a small amount of fluffed up cotton on the bottom of plastic box, and then squeeze on
the daphnia.
3. Put the slide under scanning power (red) on the microscope and find the heart near the back of
the daphnia. Determine the heart rate.
Data/Results:
Questions:
1. Exactly how will you determine heart rate? (Count for 2 min, 1 min, 30 sec?)
(did you know if the heart rate is fast you could count every other beat then double the
total?)
2. How much drug will you use?
3. Does water have an effect on the rate?
4. Do all daphnia have the same heart rate? Will this affect your conclusions?
5. Is one trial enough to give you good results or do you need to make multiple trials?
6. Should you use the same daphnia over and over?
7. Do you have a control for a comparison group?
8. If Moe and Curly took a drug and their average heart rate was 92 beats/min and
Dewey and Louie didn’t take a drug and their average heart rate was 66 beats /min – can you
conclude Dewey and Louie are in better shape than Moe and Curly?
9. If you do multiple trials, should you use the same daphnia, do you need to change the
water between trials.
Analysis/Conclusions:
Summary: