The Effect Of Ph Levels On Daphnia

Mann-Whitney U statistical testing was performed to see if the result obtained for the difference in heart rate of Daphnia before and after the addition of stimulant was significant. The statistical test for the difference in heart rate of daphnia observed after the addition of aged water is shown on table 2:

After the Daphnia was given time to calm down, the team took a reading of its heart rate at room temperature (27 degrees C). The reading was taken by counting the heart beats for ten seconds and then multiplying by six to yield beats per minute. Next, a glass Petri dish was filled with ice water at five degrees Celsius. The cold water Petri dish was placed on the stage of the microscope, and the Daphnia was placed on top of the dish. When the Daphnia had been given a minute to acclimate to the changes, another heart rate reading was taken. Then the same procedure using the Petri dish to changed environmental conditions was used with cold tap water (23 degrees), warm tap water (30 degrees), and hot tap water (45 degrees). A heart rate reading was taken for each temperature.

Week three the daphnia are tested under different concentrations of an herb to see if the herb causes any types of stress on the variable. All of the same methods are done as in week one and two except in preparing the herbal solutions. To prepare the herbal solution the herb needs to be grinded mixed with methanol and left to sit for a few minutes so it can react and separate the important contents of the herb out. In large clear wells the mixture is measured in microliters of 500, 50 and 5, we also measure out 500 of methanol and all of these are left to dry out. Then 5ml of water is added to 5 wells the four

After the results were recorded, the cavity slide was removed and placed on the working bench. The daphnia was then removed using a pipette and placed in an open container filled with a caffeine concentration of 0.2%. The Daphnia was left in there for 1 minute so it could adapt to the new environment.

The problem that needed to be solved for this experiment was, “How are organisms able to survive and function with proficiency despite metabolic activities that have the disastrous ability to alter pH from a neutral to an acidic or basic environment?” This question needed to be answered by testing different biological materials, as well as tap water, in order to find out what allows modern day organisms to survive such hazardous conditions. A hypothesis that was formulated before experimenting was, “If type of substance is Tap Water, then the changes in pH will be more drastic because water, considered neutral on the pH scale, doesn’t contain a component that will prevent such a change, unlike the content of a buffer solution.” The independent variable for this experiment was type of substance, evidently because this was the part of the experiment that was constantly being changed from trial to trial. The dependent variable for this experiment was pH of the substance because the pH constantly changed depending on the type of substance was being experimented with. The control of this experiment was the tap water and buffer solutions, as the results of the data from the biological materials were constantly compared to the data from both of these solutions.

The purpose of this lab report is to discover the exact effect caffeine has on the Daphnia’s heart rate per minute based on the day at my partner and I have collected from the experiment.

The Effects of Alcohol on Daphnia magna In this experiment I tested for the effect of alcohol on the Daphnia magna’s heart rate. I tested for alcohol and let water be the control to see the difference in heart rate. I hypothesized that alcohol will increase the heart rate of the D. magna, and my results positively supported my hypothesis. Introduction:

The uptake guarantees that the species is able to respond to the loss of ions due to the hypo-osmotic medium. This is intensified due to the high surface to volume ratio the Daphnia have. The rate in which the organism is affected is dependant primarily on the size of the daphnia and determines the species sensitivity to ionoregulatory toxicants (Bianchini & Wood 2007).

These findings were consistent with Gerristen’s findings. In another experiment though, he placed a hormone that is created by the Daphnia’s natural predator to simulate that there was a predator in the mesocosm. Glaholt determined that Daphnia would swim deeper into the cold water to avoid the hormone of their predator (Glaholt et al. 2016). A future study can be conducted to allow a better understanding of Daphnia, and how far they are willing to go to avoid

The five substances are which determined the outcome of the HR of each Daphnia. The methods that were conducted in the lab procedure are as followed: Step one the group got out the microscopes and obtained one depression slide. Using a dropper Chelsea gathered one Daphnia and placed it in the middle of the slide. Step two while the Daphnia was on the slide, Chelsea began to position the microscope to place the slide and the Daphnia in the middle of the lens to get a better view of the Daphnia and its heart. Step three, the group gathered all five substances starting with the sleeping pill.

The purpose of the lab is to see the effect of different light on daphnia magna and how they are attracted in different color. After we calculate the over all in percentage and divided by the tree to see the light which they were most attracted to. We used daphnia magna (see in figure 1) in our experiment.The different types of lights we tested were red, green,white and UV lights,(see in figure 2). It’s good to know how the behaviour of the daphnia respond. The different types of lights are which is Red light is a warning signal; especially a red traffic signal,Green light authority or permission to proceed,white light is light composed of a wide range of electromagnetic frequencies and that appears colorless to the eye and Ultraviolet or

The experiment took place in a laboratory setting, and the first step was obtaining sixty individual Daphnia magna (that were neither adults nor tiny offspring) from a large tank in the lab. These individuals were equally divided into three groups; low density, medium density, and high density. The twenty Daphnia assigned to the low density group were split into four groups of five and pipetted into one of four tubes filled with 10mL of Chlamydomonas algae. The twenty Daphnia assigned to the medium density group were split into two groups of ten and placed into one of two tubes also filled up to 10mL with Chlamydomonas. The final twenty Daphnia were all placed into a single tube filled with 10mL of the algae. In order to avoid suffocation-related

In the second experiment in which I used acid and base an my experimental factors. Using the C1V1=C2V2 formula, to measure the different concentrations of the base and acid. Through the calculations that I did, I was able to find three concentration of each the acid and the base. A 1mL , 10mL and 100mL acid concentration and the same concentration for the base. In addition, using this different concentrations, I repeated the procedure I did in the first experiment for each mL of concentration that I measured. Pay attention to the daphnia when it is on the glass slide. One should check it every one minute to make sure that the daphnia is still alive. This is different from the ethanol and caffeine experiment in which I checked how each daphnia

Data obtained from the execution of the experiment (which is described in-depth in the actual publication) indicates that the pH electrodes and the excellent pH response by AEIROF make them very helpful in cardiovascular investigations. For future experiments, materials such as stainless steel and graphite are being tested as alternative substrates for the AEIROF to provide greater flexibility in pH electrode

For this experiment, a pH meter was used so this part of the experiment began with the calibration of the pH meter with specified buffers. The buret was then filled with the standard HCl solution and a set-up for titration was prepared. 200g of the carbonate-bicarbonate solid sample was weighed and dissolved in 100 mL of distilled water. The sample solution was then transferred into a 250-ml volumetric flask and was diluted to the 250-mL mark. The flask was inverted several times for uniform mixing. A 50-mL aliquot of the sample solution was measured and placed unto a beaker. 3 drops of the phenolphthalein indicator was added to the solution in the beaker. The electrode of the pH meter was then immersed in the beaker and the solution containing the carbonate-bicarbonate mixture was titrated with the standard HCl solution to the phenolphthalein endpoint. Readings of the pH were taken at an interval of 0.5 mL addition of the titrant. After the first endpoint is obtained, 3 drops of the methyl orange was added to the same solution and was titrated with the standard acid until the formation of an orange-colored solution. Readings of the pH were also taken at 0.5 mL addition of the titrant.