How does caffeine affect the heart rate of Daphnia?

Mohamed Ahmed Does caffeine affect heart rate? The purpose of this experiment is to investigate the effect of caffeine on the heart rate of Daphnia (water fleas). Daphnia are tiny aquatic invertebrates that are suitable for this experiment because they’re abundant, easily obtained, transparent and have very simple nervous system. Hypothesis: I think that a Daphnia subjected to a caffeine solution will show a rise in heart rate, this rise in heart rate should reflect the concentration of caffeine in a given solution. This is because caffeine is a stimulant that speeds up the body affecting the nervous system and rate in which the nerve pulses are sent and received in humans. I produced a detailed plan for an experiment that allowed me to test my hypothesis using the following materials: . Pipettes 2. Test tubes 3. Stop clock 4. Microscope . Daphnia 2. Cavity slides 3. Distilled water 4. Caffeine solutions 5. Cotton wool Plan: . Use a range of caffeine solutions of different concentrations and a control solution that has no caffeine in it at all (so I have a set of results that I can compare to) 2. Place a few strands of cotton onto the cavity slide; this will help restrict the movement of the Daphnia making it easier to see under the microscope. Using a pipette transfer one Daphnia into the dimple of the cavity slide. 3. Place the slide onto the stage of a

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  • Level: AS and A Level
  • Subject: Science
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Biological Cycles

One of the main biological cycles is the nitrogen cycle, in which nitrogen is used and regenerated in four stages. Nitrogen fixation is when nitrogen gas in the atmosphere is turned into ammonia by Rhizobium bacteria and this ammonia can then be used by plants. The bacteria are found on root nodules of legimous plants, and the two form a mutualistic realationship. In return for the bacteria supplying the plant with ammonia, the plant supplies carbohydrates for the bacteria. The next stage is ammonification where nitrogen compounds from dead organisms and also animal waste is turned into ammonium compounds by decomposers such as saprobiotic bacteria. The third stage is Nitrification where ammonium compounds in the soil are changed into nitrogen compounds that can then be used by plants. First nitrifying bacteria change ammonium into nitrites, then other nitrifying bacteria called Nitrobacter turn nitriles into nitrates. Denitrification is when nitrates in the soil are converted into nitrogen gas by denitrifying bacteria, During this process the bacteria use nitrates in the soil to carry out respiration and produce nitrogen gas which then goes back into the air. This only happens under anaerobic conditions e.g in waterlogged soils. Another crucial biological cycle is the carbon cycle. All organisms need carbon to make essential compounds, therefore it is important that it is

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  • Level: AS and A Level
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Effect of caffeine on heart rate on Daphina

Effects of caffeine on the heart rate of daphnia Aim: to observe the effects of different concentrations of caffeine on the heart rate of daphnia. Null hypothesis: caffeine has no effect on the heart rate of daphnia. Alternative hypothesis: as the concentration of caffeine increases so does the heart rate of daphnia. Scientific background: Caffeine is a nerves cell stimulant that increases heart rate by the stimulation of cardiac cells. Caffeine does this by blocking adenosine, a neurotransmitter that allows the body to relax. This blockage results in the adrenal gland to release adrenaline hormone, this causes the heart rate to increase, pupils to dilate, your muscles to tighten up, and glucose is released into the blood stream for extra energy. Caffeine also increases dopamine; this activates pleasure parts of the brain which activates the caffeine addiction. Over excess drinking of caffeine could result in restlessness, headaches, and increases blood pressure. Over a long term as the body gets used to the amount of caffeine, it needs higher concentrations for more energy, releasing more and more hormones. This experiment is useful because it proves that caffeine is a stimulant that affects the heart and body, excess drinking of caffeine can be very harmful to the body as it could increase chances of cardiovascular disease. Equipment and justification: Culture

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  • Level: AS and A Level
  • Subject: Science
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What Is The Effect Of Caffeine Of The Heart Rate Of Daphnia?

What Is The Effect Of Caffeine Of The Heart Rate Of Daphnia Ross Kalarus Candidate Number: 3052 Daphnia is a small freshwater crustacean; these creatures are known as water fleas they have no physiological way of regulating their body temperature, this means once the temperature of the environment they are in changes their body temperature changes. The carapace of daphnia is translucent which makes them excellent subjects for this experiment as with a microscope you can see the heart. Anatomy of a Daphnia . In humans caffeine acts as a stimulant as it increases the amount of stimulatory neurotransmitters which are released. Some neurotransmitters released are norepinephrine and adrenaline which are the neurotransmitters that are involved in ‘Fight or Flight’ response which is directly involved with increasing heart rate. Caffeine is found in many sources in modern society such as coffee, tea, sports drinks and some chocolates. High levels of caffeine intake have been linked to restlessness, insomnia and anxiety, this can cause to raised stress and blood pressure. This can lead to heart and circulatory problems. A picture of the structure of caffeine can be seen below. The chemical formula of caffeine is (C8H10N4O2). 2. Hypothesis: Caffeine increases the amount of neurotransmitters released which increase heart rate, so as the caffeine solution

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  • Level: AS and A Level
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Malaria Issue Report

The Issue/Problem The issue I am going to be talking about in my report is about how to prevent the transmission of malaria around the world. Malaria is a mosquito-borne, climate sensitive disease caused by the parasite Plasmodium.[1] Malaria is caused by one of four species of the protoctist Plasmodium[2]. The Plasmodium parasites multiply in red blood cells; this can cause symptoms such as fever and headache, but in severe cases the disease can lead to death. Transmission Malaria is transmitted through the bite of an infected female (Anopheles) mosquito; although it can be transmitted through contact of infected blood but this is very uncommon.[3] The cycle of malaria is an Anopheles mosquito bites an infected person; a small amount of infected blood is taken. The plasmodium parasite grows and matures in the mosquito's gut for approximately a week before it then travels to the mosquito's salivary glands. When the mosquito next bites someone, these parasites mix with the saliva, are then injected with the bite, and the transmission of malaria is complete.[4] Cycle in the Body Once in the blood, the parasites travel to the liver and enter liver cells, to grow and multiply. After some time, the parasites leave the liver cells and enter red blood cells. In the red blood cells the malaria parasites continues to grow and multiply. After they mature, the infected

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The Effect of Caffeine on Daphnia Heart Rate

The Effect of Caffeine on Daphnia Heart Rate Daphnia, commonly known as water flea, are planktonic crustaceans. They are between 0.3 and 5mm in length. The life span of a Daphnia is does not exceed one year and is mainly temperature dependant. They are mainly found in lakes and are herbivorous often feeding on small green algae. In any inland water they are one of the major food sources for larger fish. Caffeine, often found in tea, coffee and cocoa is used as a flavour enhancer, it has medicinal uses in aspirin and is often found in weight loss drugs. It is a stimulant often seen in drinks like Red Bull. In humans caffeine is a stimulant drug which causes the increase in stimulatory neurotransmitters to be released. Caffeine at high levels of consumption have been linked to insomnia, anxiety, restlessness, blood pressure and raised stress. This can all lead to heart and circulatory problems. The effects of caffeine on the heart rate of Daphnia can be investigated by putting Daphnia in a caffeine concentrated solution and then taking them out to put under a microscope. The unique structure of Daphnia allows us to measure its heart rate by the amount of times their legs move. The experiment is to find out the effect that caffeine has on the heart rate of Daphnia. My hypothesis is that the higher the percentage caffeine solution the faster the Daphnia heart rate. The

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  • Level: AS and A Level
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Infectious Diseases - Avian Flu

EPScie120 2013 Major Report Bird Flu (Avian Influenza) . Aetiology and History of Disease Bird Flu or known formally as Avian Influenza or Avian flu which refers to an infectious strain of disease that most commonly affect the avian group (birds). Avian influenza can be split into two main Pathogenic groups highly pathogenic (HPAI) and low pathogenic (LPAI) strains, depending on capability to cause disease amongst poultry. The highly pathogenic avian influenza is very rarely found in humans, but can ultimately lead to severe causes of death. Low pathogenic avian influenza which is a naturally occurring infection is found to infect wild poultry, and is not an imminent threat. (FOA.ORG, date accessed 14/5/2013). Avian Influenza is still uncertain as to how people may get affected, but it is commonly transmitted through various groups of birds. The reason it’s uncertain as to why humans may get affected is that it’s not air-borne, according to (Virol et al., 2007-2008) suggests close contact with infected poultry, even the droppings is considered the main form of transport by the H5N1 virus. These cases were human infections occur in is people is in the poultry farmers working, killing and handling poultry e.g. chickens has shown to have a vast number of cases in that particular community. There have been many outbreaks of

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  • Level: AS and A Level
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Explain how the digestive, cardiovascular and respiratory systems are interrelated

Explain how the digestive, cardiovascular and respiratory systems are interrelated There are many systems within the body; all the systems have to work with one another in order to keep the body going and functioning as it should. The respiratory system, cardiovascular system and the respiratory systems are one of the few systems that are interrelated within the body and that work together in order to keep the body functioning. The respiratory and cardiovascular system both interrelate within the complex system of the human body, as firstly the oxygen that enters the body is inhaled and enters the respiratory system. This oxygen then travels through the trachea into the lungs following on to the alveoli and diffusing through the alveolar wall. This is so that it can then go through the capillary wall and enters into the cardiovascular system. The oxygen that travels and diffuses through the respiratory system then reaches the cardiovascular system. These two systems work very closely together to ensure that every tissue within the human body receives oxygen, and that carbon dioxide is removed from the body. The oxygen that is breathed in is transferred to the blood; this blood is then circulated by the heart. This then oxygenates blood throughout the body from the lungs. The digestive system is also another system within the body that interrelates with the respiratory

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The Ozone Layer.

The Ozone Layer Introduction Since the mid 1980's scientists have been aware of the continuing depletion occurring in the ozone layer. First discovered over the South Pole, these holes are thought to be the cause of excessive use of chlorofluorocarbons (CFC's, found in aerosols and refrigerators) and emissions from the petrochemical industry. Ozone (O?) itself is a highly reactive and unstable form of oxygen found in the stratosphere, but, while poisonous to humans if inhaled, it is also our natural defence against UV radiation. As people become more aware of this worsening problem and the effects of UV on the skin the demand for more effective chemical sunscreens has intensified - enter the chemists. Aim The aim of my investigation is to try different sun blocks of the same brand (differing factors) to test their UV blocking properties and attempt to identify the active ingredients used. I'll also test some household products for their UV blocking effectiveness. My results should then help me answer the question, "what makes a good sunscreen?". Research Ultraviolet Light... (1) UV radiation reaches the earth's surface in two types: UVa - wavelength between 320 - 400nm UVb - wavelengths between 280 - 320nm UVc is wavelength 200 - 280nm, however, this doesn't reach the earth's surface as the stratosphere absorbs it. The Effect Of Light On The Skin... The above

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Investigating the effect of caffeine on the heart rate of Daphnia

Core Practical Write Up Testing the tensile strength of celery xylem and vascular bundles Planning I am going to be testing the tensile strength of celery's vascular tissue with and without sclerenchyma and comparing it to see how the sclerenchyma affects the overall strength of the vascular tissues. Dependant variable: The dependant variable in this experiment is the mass/force needed to snap the vascular tissue strands. This will be measured by slowly placing masses on the end of the tissues until the strand snaps. We will then count up the mass added to the vascular tissues. Independent variable: The independent variable is whether or not the vascular bundle will include sclerenchyma or not. 3 groups are going to be testing without the sclerenchyma and 4 groups are going to be testing with the sclerenchyma. Controlled variables: We are going to be controlling the length of vascular tissue used which will be kept at 15cm throughout the class. The batch of celery used is also going to be controlled as much as we can use the celery from the same bunch each time. The method to hang the weights from the tissues is also going to be kept the same through the class room because different ways of attaching weights can add pressure to the vascular tissues in different areas making it break at different times possibly. Hypothesis: I believe the vascular tissues tested with

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  • Level: AS and A Level
  • Subject: Science
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