Daphnia: Heart Beat

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Aim:
The aim is to investigate the heart beat of the Daphnia per minute and also see the influences that solutions such as coffee and coca-cola has got on its heart beat. The affect of the tempreture on the heart beat is also investigated.

Introduction:
Daphnias are small tiny small aquatic crustaceans that are cold blooded [ means that their body tempreture would be as same as their environment tempreture ]. Daphnias are between 0.2 mm and 5 mm which means that they could easily be seen by a naked eye.{2} Another reason that Daphnias are really good for investigating, is their size and also its heart beat could be easily seen which is another good advantages that allows us investigate the effect of the alcohol, coca-cola and coffee on the heart rate. Daphnia’s heart beat is around 80 beats per minute under normal conditions{3}

You could see the daphnia in the picture below:

Methodology:
1. The pippet should be used to transfer the Dephnia from the baker onto the slide with a little bit of water with it. 2. The slide is placed under the microscope and the microscope is focused on the Dephnia so the heart beat would be cleared to be counted. 3. Its heartbeat in different tempretures is counted for 10 seconds and then multiplied to 6 in order to measure the heartbeat per minute. 4. The results are recorded in table .

5. Also for finding out the effect of coffee and coca-cola, the daphnia was placed onto the slide as same as the previous method however after that coffee/coca-cola was added. 6. The results were also recorded in the table.

Results:
The first experiment:
Column1| tube 1| tube 2| tube 3| tube 4| tube 5|
temperature [?C] | 0| 12| 20| 25| 40|
heart rate [bpm ]| 156| 228| 246| 228| 0|

In total daphnia’s heart beat increases as the tempreture increases but not in all tempretures. As it is shown in table 1, from 0 oC to 20 oC the heartbeat increases as the tempreture goes up and after 20 oC...
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