Immediate Submersion

One Minute submersion

Immediate submersion with alcohol

    Our hypothesis for the immediate submersion was that the colder the water, the more the daphnia’s heart rate would increase.  We believed these would be the results because humans shiver in cold temperatures to keep them warm. This is similar to how we thought the daphnia’s heart rate would speed up in order to pump more blood throughout the body. We also thought it would be similar to when humans suddenly plunge into the water then hyperventilate, and their heart rate increases.

    Our next hypothesis was for the extended one minute submersion. Our hypothesis was that the heart rate would stay the same through all the temperatures. This was our hypothesis because we thought that being in the temperature for one minute would cause the daphnia to calm down and become acclimated to the temperature, therefore causing the heart beat to revert back to what it was at the control.

    Our final experiment was the immediate submersion with alcohol. This experiment was the same as the immediate submersion, but with added ethanol alcohol. Our hypothesis was as the temperature decreased and alcohol was added, the heart rate would increase. We hypothesized that because going along with our hypothesis for the immediate submersion, the colder the water, the higher the beats-per-minute, and adding alcohol would intensify the hypothermia and cause the heart rate to increase.