Daphnia Lab

My group recorded higher heart rate compare to the class average when we used caffeine on the Daphnia as seen in Figure 2. Several errors could have accounted for this data. This including perhaps the Daphnia’s heart rate may have changed because of fear while being moved from the bowl to the microscope slide. Another possible error could have also been the amount of time that it took to change the solutions, which could have accounted for slight variations in heart rate. Temperature is yet a further error to account for as the microscope slide temperature was constantly changing to view the specimen, and change the dosage of caffeine or alcohol. The temperature of the solutions could also have played a factor in the Daphnia Heart rate as ideal conditions for Daphnia is 68 degrees Fahrenheit and the temperature of the solutions was not measured for.

The interesting question scientists raised is, can we relate to them? The answer is ‘yes’. For instance, the genes necessary to tell a plant whether it is light or dark, time cell division, and promote the proper functioning of the immune system are contained within the human genome as well. (Armstrong) “People have to realize that plants are complex organisms that live rich, sensual lives.” (Scientific American) Plants smell, taste, feel pain, have memory, and communicate. Orchids give off a human body odor to attract mosquitoes and plants that cannot stay alive through photosynthesis live off other plants. They find ways to avoid incest through complex internal warning systems and desert plants have been known to gamble as humans do, even when it means they take on greater risk in the process. (Pennisi) Jahren states that the cholla cactus had an ‘idea’ to grow a spine, (Jahren 64) the process of evolution took millions of years in that case. They exhibit patience and foresight to make up for their rootedness. The fact that plants remain rooted to the ground causes the misconception that there is nothing going on within them. Yet, this only means that they have developed through evolution to ward off parasites, reproduce, and find food in ways unique from the organisms in the animal

A cigarette is made up of seven thousand chemicals but one of the worst because it is addictive is nicotine. Once the nicotine is breathed in it is absorbed into the bloodstream and within twenty eight seconds it goes into the brain. There are major problems with nicotine entering into the body. First of all not only does the nicotine enter into the brain, but once it is in there it attaches to a neurotransmitter called acetylene and mimics what it is supposed to do, which is control muscle movement, breathing, and the heart rate. However what makes nicotine addictive is when it released to parts of the brain that produce pleasure. Scientists have recently discovered that nicotine raises the level of a neurotransmitter called dopamine, which is a part of the brain that produces pleasure. Another problem with nicotine getting inside the body is the fact that is actually a chemical and it is used as a bug repellent or eliminator.

Four randomly selected Daphnia magna, for each trial, were removed from the provided colony for the bioactive compounds to be tested, and were transferred with a plastic wide-mouth pipette with approximately 10 mL of pond water to protect and ensure survival of the Daphnia. In order to acclimatize the Daphnia to laboratory conditions, they were then placed onto a petri dish on the Daphnia cooling chamber. The cooling chamber was located on the stereomicroscope platform and brought down the heart rate of the Daphnia to a range that was countable by the observer, since Daphnia heart rate at room temperature is too rapid. On the cooling chamber there were two petri dishes: one for the Daphnia that were going to be tested, and one with the Daphnia being tested on, to ensure constant consistent temperatures for each trial. To maintain a temperature conducive to the heart

The mimosa is a prime subject for this testing as its reflex behavior is observably quick enough to document the reactions; upon contact, the fernlike leaves of the plant recoil from the touch. This behavior is likely used as a defense mechanism to scare off insects but in the study, it was used to measure the plants’ responses and help to conclude if they were adapting to the conditions. The experiment Gagliano conducted tested nearly five dozen mimosa plants’ reactions to being dropped a small distance every few seconds. Gagliano noted how the organisms initially reacted by folding up but after only a few drops, the leaves began to reopen. The ecologist took this as evidence that the mimosa plants recognized that there was no harm in this particular movement and “had concluded that the stimulus could be safely ignored” (Pollan). Furthermore, the Australian scientist went on to retest her plants over the course of twenty eight days, to which they remembered it was safe to ignore the

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. The hypothesis for this experiment is that if daphnia are exposed to ethanol, aspirin,

Daphnia are grown as fish food, and used to test ecotoxicity. Ecotoxicology is defined as, "the branch of toxicology concerned with the study of toxic effects, caused by natural or synthetic pollutants, to the constituents of ecosystems, animal (including human), vegetable and microbial, in an integral context” (Truhaut, 1977). The experiment discussed in this lab report was performed on daphnia, exploiting their transparency which renders them the ideal organism, to test effects of various stimulus on cardiac activity. Past research studies have found ethanol to produce a depressant effect, one similar to the depressant effects of melatonin, and GABA. In contrast, Corotto (2010) has experimented on stimulants, e.g. nicotine, and found an approximate 20% increase in HR. 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 Honors Earth Science classes went to the Susquehanna River to solve a problem. The problem was not knowing if the is healthy. The classes want to know if the river is healthy, because the students live near the river, and it affects the classes everyday lives. To answer the problem, the classes did a series of tests, and made physical observations at various islands in the river. The students used test kits and other tools to test pH, temperature, phosphate, nitrate, turbidity, and dissolved oxygen. The results of the tests were that the Susquehanna River is indeed, very good and healthy. It was discovered that temperature directly corresponds with dissolved oxygen. It was also discovered that there are different types of fish that live in different temperatures.

The objective of this study was to test the phototactic response of Daphnia when exposed to red (>600 nm) and white light. A 30 x 2 cm clear acrylic mesocosms with a 10 cm counting area was filled with distilled water and 10 Daphnia. We counted the number of Daphnia that traveled to the lit counting area after 10 minutes. There were twice as many Daphnia in the lit counting area for the control (white light) compared to the experimental group (red light). The results showed that red light had a negative effect on the phototaxis of Daphnia.

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. After allowing the worms to be treated for fifteen minutes, they were briefly rinsed and placed in the viewing chamber to measure their pulsation rate. This was done three times for each worm to calculate a mean rate for first level of treatment, 3.0 mM of caffeine. The same procedure was repeated for part II of the lab, however; a different set of three worms were treated with nicotine and all the means were collected to calculate the standard deviation of each

Question: Can Daphnia be used to detect water pollution? How does the water type (source) affect the number of Daphnia and the accuracy and efficiency of testing water safety?

Senior year is said to be the best year of high school. It was for me, until I earned my first detentions. During second hour, Mr. Breazeale, the school superintendent, called me out of class. He stated that the police dog was sniffing out cars in the parking lot, looking for anything suspicious. He said the dog showed interest in my car. He thought it was nothing, but they still needed to search my car. It was parked in the student lot surrounded by office staff, our school police officer, and a lady with her trained dog. They saw beer and pop cans through the clear window of the trunk of my car. However, she claimed she was required to search my car. After I unlocked the doors, she began going through all the compartments inside the car and that’s when it dawned on me.

Respiratory Disorders: Another concerning symptom of presentation to or ingestion of pesticides are respiratory issue, including wheezing, endless bronchitis, asthma and agriculturist's lung. Normal presentation to pesticides expands your danger for creating respiratory issues, however can be reduced with fitting respiratory assurance and every day precaution

Plants are a major necessity in the balance of nature, people’s lives, and our terrain. We may not realize it, but plants are the ultimate source of food for almost 95% of the world population so says the National Group of Food. It’s a fact that over 7,000 species of plants are being consumed today.