What follows are some suggestions for simple experiments that will work even if one has little experience with Daphnia parasites. 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. In this experiment we will intoxicate an organism. Transfer to a depression slide and add water. 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. Like other arthropods, its heart is on its back. The more transmission stages that enter a host, the more competition will occur, thus lowering the success of each individual parasite.
The wide range of parasites available allows for the testing and comparison of epidemiological, evolutionary, and genetic models of infectious diseases. The acetic acid was used as a catalyst to speed up the reaction. It will be directly proportional to each other, meaning that the increase of the concentration of the caffeine will give an increase of the heartbeat. The solution team could have forgotten to use a Kimwipe to remove an alcohol solution from the Daphnia. First a zero reading was taken before any chemicals were introduced. Throughout the rest of the experiment, the heart rate stayed between 200 and 180 beats per minute.
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. As well as different volumes of caffeine. The reading was taken by counting the heart beats for ten seconds and then multiplying by six to yield beats per minute. These follow the common epidemiological assumption of mass action nicely, which states that the likelihood of transmission is strictly a function of the population densities or sizes of infected and uninfected hosts. Daphny Maldonado Bio Lab 2107 Kiah Britton W 10-12:30 Is H20 Bad for You? Lab reports; and to conduct your own independent project. A pipette was used to place the Daphnia with water on a glass slide. Because all treatment groups are infected, an uninfected control does not seem necessary.
When doing the experiment the first step was to take the Daphnia and put it a Water solution to observe the heart rate of the Daphnia and record the heart rate. After the epinephrine was diluted from the slide the average heart rate returned to an average of 78 beats in 15 seconds, with a decrease of 7% from the heart rate with epinephrine. The experiment tested phosphorus at five. Caffeine has additional effects on the heart. Record the number of heart beats in the data table on the next page.
We can observe the heart of the Daphnia to be dorsal to the backbone, just behind the head. After placing the Daphnia in warm water the average heart rate went up to an average of 72 beats in 15 seconds, with an average increase of 12. After the epinephrine was diluted from the slide the average heart rate returned to an average of 78 beats in 15 seconds, with a decrease of 7% from the heart rate with epinephrine After putting the Daphnia in warm water the average heart rate increased by 12. Large hosts suffered from higher mortality than smaller hosts, which significantly reduced the mean body length in the starved populations. Establish the resting heart rate of the Daphnia. The next part expands to discuss experiments that use entire populations as the unit of replication. Once the solution becomes bright green, it contains billions of algal cells and is ready for use as Daphnia food.
Methemoglobin is not a problem in adults since they have an enzyme that converts methemoglobin back to hemoglobin. If the effect of the actual treatment and the effect of the placebo treatment do not influence each other, this is not a problem, but if the effect of the placebo interacts with the effect of the actual treatment, the results may be difficult to interpret. We will observe the effects of temperature fluctuations, alcohol, and caffeine on this ectothermic animal. First, it could have been experimental error. This means that there will be more blood flow to skeletal muscle in which exercise causes dilatation of blood vessels , so the skeletal muscle cells are supplied with more oxygen and respiratory substrates used to generate energy in respiration where it is needed.
Put each key word or phrase in a separate box to increase your results, as below: Articles with , , or icons can be read and printed with one click. The ethanol before further dilution should be 10% ethanol. Conclusion Our results show a curve of 0% concentration being higher than 0. LaFave, 2003 This can be explained by the excessive nervous system inhibition caused by the alcohol. If too much alcohol is added, it will result in the death of the animal. Learning to write laboratory reports will provide you with a valuable and transferable skill. Marshall Cavendish, 2002 Daphnia have a hard external skeleton with jointed appendages and limbs.
Risk assessment Risks Prevention Caffeine Concentrations in eyes or spillages onto clothes Caffeine concentrations could splash into the eyes causing irritation, this could be prevented by wearing goggles. The alcohol acts by inhibiting the nervous system. In particular, the heart rate will get consistently lower. It is important to think ahead about the way in which the populations are sampled, because sampling itself may introduce some effect. Because of the variability of results between individual Daphnia, it is not appropriate to draw conclusions from one set of results; each pair or group of students should carry out more than one investigation to contribute to the class set.
Daphnia are crustaceans, commonly found in ponds and lakes and widely sold as live fish food. Host Starvation and Parasite Load in Experimental Populations Outbreaks of in vertebrate have often been linked to host stress. Experimental Epidemiology and Evolution of Daphnia Parasites An alternative to experiments on individuals is to investigate the effect of on their host. Variables: temperature, sugar, artificial sweetener, caffeine. Occasionally add more water and fertilizer to replenish the algal solution after feeding your Daphnia cultures.