Daphnia, also known as water fleas, are small aquatic crustaceans that are commonly used as model organisms in scientific research. One area of research involving daphnia is the effect of ethanol on heart rate. Ethanol, also known as alcohol, is a psychoactive drug that is commonly consumed in beverages such as beer, wine, and spirits.
The heart rate of daphnia can be affected by various factors such as temperature, pH, and the presence of chemicals or drugs. Studies have shown that ethanol can have a significant impact on the heart rate of daphnia. In general, ethanol has a depressant effect on the heart, which means it slows down the heart rate. This can be seen as a decrease in the number of beats per minute.
One study found that exposing daphnia to a high concentration of ethanol (500 mg/L) resulted in a significant decrease in heart rate. The heart rate decreased by about 50% after 30 minutes of exposure to ethanol, and this effect persisted for at least two hours. Another study found similar results, with a decrease in heart rate of about 35% after 30 minutes of exposure to ethanol at a concentration of 250 mg/L.
There are a few potential mechanisms that could explain the effect of ethanol on daphnia heart rate. Ethanol may alter the activity of certain ion channels in the heart, which can affect the rate and strength of contraction. Ethanol may also affect the release of neurotransmitters, which play a role in regulating heart rate.
In addition to its effect on heart rate, ethanol can also have other effects on daphnia. For example, ethanol can affect the respiratory rate and metabolism of daphnia, as well as their swimming behavior and ability to reproduce.
Overall, the research suggests that ethanol can have a significant effect on the heart rate of daphnia. This finding is consistent with the known effects of ethanol on the human heart, which can also slow down the heart rate. However, it is important to note that the effects of ethanol on daphnia may not necessarily be the same as the effects on humans, as daphnia and humans are different species with different physiological systems.
Re: Why does ethanol slow down the heart rate of Daphnia?
To do this you will need the small syringe, and 5 Petri dishes. Unfortunately, there is not a lot of documentation of the mechanisms by which alcohol slows down Daphnia heart rate. Put a 0% label on the Petri dish in order to keep track of the different concentrations you will be making. The nerve fibers conducting pulses to the hearts of Daphnia may contain receptors that inappropriately bind to ethanol or a product of ethanol after it is broken down causing an inappropriate decrease in nerve activity. However, because it is difficult to perform experiments of this nature on humans and get accurate results, we decided to use Daphnia Magna as a substitute for a human. The effects of alcohol and caffeine were a distinct interest sense they are drugs that are consumed on a large scale in society. In future, the experiment could have been done on one day.
Effect of Alcohol & Caffeine Concentration on Daphnia Magna
Proof of model validity emerges only once human data sets are available. If ethanol is added to the environment of Daphnia, then the number of heartbeats per minute of daphnia will decrease, when compared with control solution of distilled water. This will be the independent variable. Then I'll go into a more detailed answer. People who are take aspirin long-term for medical reasons because they have cardiovascular disease or diabetes may have a lower heart rate than controls, simply because they experience less coronary and peripheral thrombosis and thus have a better lubricated cardiovascular system. Considering that their heart beatwas approximately 200 bpm at normal temperature, the data was quite accurate in terms of the average bpm.
Use tissue to remove excess fluid. Draw the pond water off the Daphnia with a pipette and replace it with 2 or 3 cm 3 of the water containing ethanol Note 3. The next Petri dish will contain 0. By reducing the ability of platelets to adhere to damaged blood vessel walls, aspirin reduces the chance of coronary artery thrombosis, the event that precipitates a heart attack. With a small syringe, take 10 ml of distilled water the use of distilled water is important as you will be removing any materials that may have an effect on the Daphnia heart rate and place it in the Petri dish. Daphnia are small aquatic crustaceans that live in freshwater environments. The effect of temperature on a metabolic activity may be expressed in terms of the temperature coefficient Q 10.
Effects of melatonin and ethanol on the heart rate of Daphnia magna · 2009
Work your way up from 0% to 0. Keeping a few Daphnia is not difficult, but cultivating a vigorous, dense colony requires some care. Overall, the first and second trials both suggested that the results were quite similar as for distilled water in trial one the result was 150 bpm and in trial two the result was 138 bpm. Count the heart rate of the Daphnia when placed in all the concentrations. Conclusion They allow communication between cells to occur. We hypothesized that the addition of caffeine to the Daphnia would cause an increase in their beats per minute, while the addition of ethanol would cause a decrease in the beats per minute of the Daphnia. This allows the changes in Daphnia heart rate to be studied quite easily.
Alternatively, you can buy food such as Liquifry No 1 or Spirulina powder from aquarists or scientific suppliers. Using the pipette to collect Daphnia from the main source into a petri dish. Then you replay the video in slow motion and count the heart beats again. Heat may modify the Daphnia heart rate, and the effect of heat on the heart rate is not the purpose of this experiment. Ethical issues Teachers should be careful to introduce these animals in a way that promotes a good ethical attitude towards them and not a simply instrumental one. According to the table of results that shows the two trials and average number of heartbeats bpm , when the daphnia was exposed to distilled water, their number of heartbeats in the first trial was 150 beats per minute, followed by the second trial with 138 beats per minute. They are tolerant of being observed live under a microscope and appear to suffer no harm when returned to open water.
Caffeine is used in everyday life for many to achieve the feeling of alertness; however, when ethanol alcohol is consumed the adverse effect is expected. It is very important to put the Daphnia in with the least water possible, in order to prevent it from moving too much. If you're interested in learning more about determining characteristics of cell membrane receptor-binding, please ask us! There are many explanations why Daphnia Magna are commonly used compared to the use of a human as test subject. The first thing that has to be done is the preparation of the different solutions where the Daphnia will be placed. To achieve this, the type and extent of the effect in humans at the same drug concentration the human template must be known. It caused their heartbeat to slow down a lot from 150 bpm decreasing to 120 bpm in the first trial. Thanks to the British Pharmacological Society for providing the teaching notes on this practical.
The Effect of Caffeine and Ethanol on the BPM of Daphnia magna
Allow the Daphnia some time to acclimatise, but keep a check on the temperature of the water in the dish and add more hot or cool pond water if necessary to adjust the temperature. Though humans and Daphnia Magna are different organisms, alcohol and caffeine should have an almost identical effect on them. Student notes Example results: Background information: chemicals and the heart Acetylcholine: In humans and many other animals, heart rate is slowed by the parasympathetic nervous system neurotransmitter: acetylcholine via activation of cell surface receptors in the sinoatrial node pacemaker called acetylcholine muscarinic receptors. Daphnia can be kept in any watertight container containing tap water that has been allowed to stand for a few days. To test this hypothesis two Daphnia Magna were exposed to either alcohol or caffeine and its heart rate recorded by placing it on a microscope slide and counting the number of heart beats. In terms of heart rate, the Daphnia sinoatrial node is actually a collection of spontaneously active nerves in a body called the cardiac ganglion.
The opposite effects of caffeine and ethanol on Daphnia magna’s heart rate
Table 4: Class data for Alcohol concentrations Initials Water Control AVG 2% Alc 4% Alc 6% Alc 8% Alc 10% Alc KR 133. Our academic experts are ready and waiting to assist with any writing project you may have. We believe that our research will catch the interest of people who are studying heart disease and the effects of drugs on the human heart because it offers new information that can assist in the creation of cardiac muscle implants, due to the Daphnia magna having a heart similar to that of humans. Aspirin : Aspirin has no effect on heart rate. Null Hypothesis : Ethanol will have no effect on the heart rate of the Daphnia. Investigating the effect of chemicals k Take a large Daphnia from the stock culture and record its heart beat at room temperature in pond water as in step e.
Investigating factors affecting the heart rate of Daphnia
Study on the Effect of Alcoholic Beverages on the Heart Rate of Daphnia Daphnia magna. Since their cytoskeleton is clear and their organs are visible, daphnia have been used to observe environmental changes and in order to determine how the change of the environment they are exposed to affects their heart rate. Count the heart rate of the Daphnia when placed in all the concentrations. The cavity slides must be allowed to cool down before using them again as they tend to heat up. Despite this, aspirin has beneficial effects in the heart. Model validation requires examination of a range of positive and negative controls for their effects in the model.
Each Daphnia will stay in the ethanol solution for exactly 3 minutes so that an equal volume of ethanol is absorbed. It is important to try to keep the temperature of the experiment as stable as possible. The experiment consisted of five trials for each solution. As a result I must ensure that I choose Daphnia which are the same size when conducting repeats. Turn the microscope on.