Research Protocol – Monitoring of the Daphnia magna heart rate The experiments focused on the four treatments of nicotine, caffeine, ethanol, and double distilled water (placebo). 180 μL of each bioactive solution (nicotine was covered with foil, due to light sensitivity) and 120 μL of double distilled water were placed into labeled eppendorf tubes to dismiss cross-contamination, and were placed on ice to match the environment of the Daphnia to reduce any added stress on the Daphnia. One Daphnia was placed on the testing petri dish, and then all the excess pond water was removed with a transfer pipette.
Daphnia Magna are small crustaceans that are excellent for observing the effect of depressants on their nervous system. The purpose of this specific experiment is to observe the effect of ethanol, aspirin, and caffeine on daphnia’s heart rate. Not only do these chemicals affect heart rate, but they also affect the frequency of reproduction, number of eggs produced, and body structure. Pesticides similar to these chemicals can be released into the environment and daphnia re useful in monitoring toxicity levels. The agents being tested in this experiment can be administered to determine the effects of hormones, stimulants, antidepressants, and neurotransmitters.
Daphnia magna is a transparent water flea species found in rocky pools along the Atlantic Ocean. The Daphnia’s body is encased in a clear structure called carapace (Elenbaas, 2013). The exoskeleton, carapace, provides protection for the Daphnia magna, “The portion of the hard exoskeleton, or shell, that covers all or part of the body of many crustaceans…” (“Definition, n.d.). The heart can be easily seen under a light microscope due to the transparency of the skin (Handy, 2012). A variety of factors can change the heart rate of Daphnia. According to Richard Handy (2012), “The heart rate (which can be up to 300 beats per minute) can be monitored and counted in different conditions – for example changing water temperature, or changing the type
Caffeine, Nicotine, ethanol, and a control solution were tested. The heart rate of Daphnia was measured after exposure to each of the chemicals. After testing, it was found that ethanol depressed the heart rate while exposed, but the heart rate stabilized after exposure. With exposure to nicotine, the heart rate increased by 20%. If more nicotine was added, the effects were varied and sometimes irreversible.
The data presented in this lab report was observed manually. In this experiment, cardiac activity is being determined via measurement of i.e. heart rate. (HR) For this experiment, the daphnia was subjected to different chemicals via submersion. These chemicals were used as stimuli to prompt altered cardiac activity. The purpose of this experiment, is to test whether two select depressants or stimulants, when administered together, produce a synergistic, antagonistic or no effect on
The following experiment determines the effects of 50 ml tobacco extract on the heart rate of a crustaceans Daphnia Magna. Daphnia represents a small group of aquatic crustaceans, also known as “water fleas”, with clear exoskeletons, which makes studying their heart rate effortlessly. The heart rate can be observed using a microscope and counted under varying conditions. (Pritchard, J. B.) In this case, changing the type and concentration of natural plant substances reveals the effects of the plant defense mechanisms on the specimen of Daphnia Magna. Tobacco (Nicotiana tabacum) was the plant chosen for the experiment. Since, nicotine in tobacco is a stimulant, it is predicted that if Daphnia exposed to this substance would have an increased
Using a disposable plastic pipet, worms were transferred with a bit of spring water to the viewing chamber and given a few minutes to settle to their new surroundings. The viewing chamber was then placed under the dissecting microscope at the lowest power, which helped with focusing on the middle body region of the worm to measure pulsation rates. Using a stopwatch, the basal rate of the worm was obtained by counting the number of pulses that moved through a segment in a thirty second interval, this amount was multiplied by two to result in units of beats per minute. Three basal rates were recorded for each of the three individuals warms to calculate their mean rate. Worms A, B and C were then placed into separate containers containing the caffeine treatment solution.
Hypotheses: Do you expect heat to be a chronotropic factor? Yes Do you expect heat to be an inotropic factor? Yes Procedure and Results: Control Heart Rate (After rinsing) beats/min Experimental procedure Heart Rate after treatment beats/min Change in Heart Rate beats/min Strength of Contraction after treatment compared to normal (stronger or weaker) Baseline rate: 72 Continuously drop warm Frog Ringer’s onto the heart 48 -24 Weaker Rate after rinsing: 72 Continuously drop cold Frog Ringer’s onto the heart 60 -12 Weaker
What is the effect of oxygen levels on the hemoglobin synthesis and coloration of Daphnia magna? Background Research Daphnia are small organisms and are sometimes known as the water flea. Some of the most common species of Daphnia are D. magna and D. pulex. When found in lakes and ponds, Daphnia are known to help filter the ecosystem. They are mostly found in lakes and ponds.
The chloroform and caffeine mixture was collected and into a conical flask labeled A. The remainder of the solution was discarded. This was repeated for beakers B and C. 9. Sodium sulphate was then added to each beaker to dry the liquid by getting rid of any remaining water from the solution. The sodium sulphate was then filtered and discarded.
From this research and literature the expected results of the experiment were to see an increase in membrane permeability, this result was observed. The study provides a brief insight into what kind of effects alcohol can have on cell membranes but it is limited. The results can be used to understand but not explain more practical applications, like human cells for example. Conclusion
Nonetheless, besides fish, many other kinds of poikilothermic animals, such as snakes and frogs, use lungs instead of gills to breathe, and further researches may be conducted to explore if caffeine has an effect on their metabolism. For example, forty northern leopard frogs with similar body size will be captured and divided into twenty trials, and each two frogs will be tested in the same control and experimental conditions as the goldfish metabolism experiment did. The collected slopes of oxygen concentration will then be converted into oxygen consumption rate and analyzed by the paired t-test. If the difference in the oxygen consumption rate between the control and experimental groups is statistically significant, this experiment will show that caffeine affects the metabolism of frogs, one kind of poikilotherms that use lungs to
Caffeine is a chemical found naturally in few plants all over the world. From these plants it is processed into its pure form and then put into other things such as soda, energy drinks, tea, and pills. Energy drinks and soda are some of the most widely marketed products in the world, even though they contain the highest concentration of caffeine outside of pure caffeine supplements. It is a stimulant that affects everyone in strange but semi predictable ways. Research has been done on this topic since the 1920’s and many different conclusions have been reached.
Whenever a consumer uses an energy drink a series of effects begin in his/her body. The organism receives an instant boost as the caffeine successfully manages to block the duties of the adenosine, a chemical located in the brain whose function is involved with sleeping. After the completion of the process caffeine forces part of the neurons in the brain to lighten up, which later on causes the body to release the hormone adrenaline. When the hormone is active it forces the liver to provide the bloodstream with additional