ACTIVITY 1: THE EXPERIMENTS ON DAPHNIA

As we know, in mammals, including humans, acetylcholine or cool temperatures slow down the rate

of heartbeat while adrenaline speeds it up. How do you think those factors will affect the heartbeat

of daphnia? Write down your hypothesis below:

During today's experiment, you will have to expose daphnia to acetylcholine, adrenalin, and cool

temperature, to count their heart beat. Since the daphnia's exoskeleton is transparent, it is possible

to watch their hearts without cutting them open. Using a single microscope, you will have to

work in pairs.

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The Scientific Method: Using a Model Organism in a Study of Heart Rate Exercise 4/nDaphnia sp.

A

B

с

D

E

Daphnia sp.

A

B

C

D

E

Daphnia sp.

A

B

с

D

E

Daphnia sp.

A

B

C

D

E

Jab file.

Beats/min

Beats/min

Beats/min

Table 4.2. Heart beats of Daphnia sp. in 1% acetylcholine solution.

Beats/min

Beats/min

Beats/min

Beats/min

Beats/min

Table 4.3. Heart beats of Daphnia sp. in 1% adrenaline solution.

Beats/min

Table 4.4. Heart beats of Daphnia sp. in the cold

Beats/min

Beats/min

Average beats/min

Beats/min

Average beats/min

Average beats/min

Average beats/min/nACTIVITY 2: WRITING THE LABORATORY REPORT

Below summarize the content of the data tables:

Did you prove or disprove your initial hypothesis? Explain.

Write your conclusion below: