Scientific Paper on a Water Flea

According to the results, the columns of caffeine in figure 1, of this experiment the hypothesis for caffeine is partially accepted. There is an increasing trend in the change of pulsation rates with increasing

Although with the addition of caffeine 1% and ethanol 1% the rate of the heart decreased and increased. The addition of the caffeine improved the daphnias heart rate by 20 beats, meaning its overall heart rate was 236 beats per minute. Whilst with the accumulation of the ethanol the daphnia’s heart rate dropped dramatically by 40 beats and only measured in at 176 beats per minute.

The following was the procedure used by the team that introduced chemicals into the environment of the Daphnia. First a zero reading was taken before any chemicals were introduced. The zero reading was an observation of the Daphnia’s heart rate before any substances were administered. All fluids were drawn off the slide using the corner of a Kimwipe. Then two drops of two percent alcohol solution were dropped onto the Daphnia. After a minute a heart rate reading was taken. The same procedure, including using the Kimwipe to draw off previous solution, was then used with four, six, eight, and ten percent solutions. A heart rate reading was taken after each solution was introduced.

In Exercise 1, diaminofluorene is used to determine the hemoglobin concentration in the daphnids. A higher hemoglobin concentration is indicated by a darker blue color. A spectrophotometer was used to determine the absorbance at 610nm. When measuring the absorbance levels a blank is necessary to have a zero reference, the blank is the “starting point” for the measurements of the sample (re-word). The blank consists of 10µL of diaminofluorene(DAF), 50µL of hydrogen peroxide, and 0.5mL of PBS. The PBS acts as a buffer in this experiment. The cuvette with the sample of daphnids consisted of 10µL of DAF, 50µL of hydrogen peroxide, and 0.5mL of the sample of Daphnia. In Exercise 2, the Pasteur pipette was used to obtain the sample of Daphnia. The depression slide used in this experiment isolated the daphnid, cotton was used to keep the daphnid still while the heartbeat was counted. The ocular micrometer on the microscope allows the tail spine length to be measured accurately, as well as using an ocular magnification table.

In order to complete this exercise, two different procedures were conducted; one measured the basal heart rate, and the other measured the drug-induced heart rate. A sample 's basal heart rate can be defined as the “resting” heart rate. This is when no drugs or altering substances are applied. In comparison, the drug-induced heart rate of a sample can be defined as the heart rate after the drug was administered to the surrounding environment. The four drugs tested on the Daphnia specimens were Acetylcholine, Caffeine,

Atropine showed the only a minor increase in amplitude and period. The BPM was the detected as increase up to 30 seconds then a drop back down to 44, then the heart rate shot back up to 48 before recovering.

The effects of caffeine and alcohol on daphnia are expressive of whether these substances are harmful or beneficial to the organism. By understanding the results of this experiment, it may also be understood how these substances effect humans. In this study, one daphnia was exposed to increasing levels of alcohol, while the other was exposed to increasing levels of caffeine, each in order to test the hypothesis that when given amounts of caffeine and alcohol, the daphnia will be affected the same way a human would. The effect of each substance was measured by the daphnia’s heart rate one minute after the substance was added. Results reveal that alcohol slows the heart rate, while caffeine increases heart rate. Furthermore, caffeine shows a

Figure 3 shows the effects of epinephrine and GABA drugs on the heart of the cray fish. In figure 3-A, it tests an epinephrine on the heart of crayfish and comparing it to the resting state. In figure 3-B, GABA drug has been tested on the heart of another crayfish after recording the results of resting state.

In this experiment we find how caffeine can affect the heart rate of a culture Daphnia. Heart rate of a living organism’s can vary depending on the individual, age, body size, heart conditions, medication use and even temperature. This report will examine if the caffeine is good or bad for the living organism’s health and body. And discuss about where the caffeine is produced and used in daily life of human beings and on the environment. Daphnia is a water flea used in this experiment because of its genomic infrastructure with wide range of phenotypic diversity. This quality of Daphnia makes them a versatile model for the experiment. Also their transparent body allows the experimenter to visually see how the heart beats and count them under the light microscope during the experiment as required. The heart rate of Daphnia is monitored under different concentration of caffeine solution and the results are shown in a table and a graph. Experiment carried out to locate the effects of caffeine on a heart rate of Daphnia may or may not be a predictor of change in human heart rate under caffeine. The effects of caffeine can also be tested on humans but those experiment involving humans contains high risk, as Daphnia can only live for a short period of time and in nature most of them get eaten within their first few days or weeks of life.

My hypothesis was, as the concentration of alcohol increases the lower the heartbeat of the Daphnia will fall. To test my prediction I carried out 25 individual experiments which were all carried out using the same procedure but varying the alcohol concentration of the solution. To investigate how alcohol concentration affects the heartbeat of Daphnia I recorded the heartbeat of 25 Daphnia for a period of 7 minutes. This included 1 minute before submersion in alcohol, 3 minutes during submersion in alcohol and 3 minutes after submersion in alcohol. I then found the percentage decrease of the heartbeat of the Daphnia from the resting heart rate.

For each test solution and base HR, the daphnia was submerged for ten-minutes to allow the chemicals to take effect, for daphnia are ectotherms and their body adapts to the surrounding environment. The data in Table 1 and Graph 1 answer the question of whether a daphnia, when exposed two depressants, i.e. melatonin and ethanol, will result in an average heart rate (HR) lower in comparison to the two depressants being administered individually. Over the three trials conducted for each of the test solution for daphnia 1, it can be concluded that 10% ethanol administration resulted in almost 2.6 fold, that is approximately 60%, decrease in HR. Therefore, ethanol had a depressant effect on average BPM, similar to Corotto's findings. (2010) Also, since the first daphnia died after

Experiment one tested the concentration of experimental beta blockers, and its relationship with the percent decrease in of the heart rate of the Daphnia. Our goal, was to prove that, an increased concentration of beta blockers would decrease the overall heart rate of the Daphnia being tested. Our results, established, that as the beta blocker concentration increased, so did the decrease in the heart rate of the Daphnia. Experiment two tested two unknown concentrations (A and D) and its effect on the Daphnia to see if it contained any concentration of beta blockers. The results, for concentration A showed very little effect, and concentration D seemed to have no effect on the Daphnia at all. Experiment one shows, that

This experiment is being performed to show the effect of pH levels on daphnia by changing pH levels and measuring the heart rate.

First, saturate the TLC trough with 30 ml of ethyl acetate: methanol solution for 10 mins. Next, spread the silica gel into into a 0.2 micrometer film over the Aluminum plate. Then, to dry the plate for usage, heat the plates in an oven at 110 Celsius for 5 min. Apply the samples 1 cm above the base of the plate using a sample applicator, along with nitrogen gas to allow the bands to simultaneously dry. Place the TLC Plate into the chromatography trough, and allow the plate to develop until the 10cm mark. Follow up by scanning the TLC plate in a densitometer to obtain a chromatogram of the separated samples. The Peak of caffeine observed on the chromatogram can be matched to the real plate and be scraped off for the retrieval of caffeine.

Now that the experiment has been tested, the results are in there comes the analysis part of the process. After I had determined my calculation I saw where my beats per minute were over a hundred; this consider me to be Tachycardia. Tachycardia refers to an abnormally fast resting heart rate. When examining what Tachycardia was and how it can be affected made me see that different scenarios will affect the beats per minute. Anxiety, caffeine, stress can all cause someone to have such a rapid heartbeat. I remember from when taking the echocardiogram that I was stressed