"The affect of caffeine on the daphnia heart rate" Essays and Research Papers

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    Abstract: Caffeine‚ (C8 H10 N4 O2) a white‚ crystalline alkaloid known as a nervous system stimulant found commonly in tea leaves and coffee‚ can be extracted using the method of sublimation with the use of Methylene Chloride (CH2Cl2) and Sodium Hydroxide; both can repeatedly rinse the green (unroasted) coffee beans from the caffeine. Keywords: Caffeine‚ Methylene Chloride‚ Sodium Hydroxide‚ Anhydrous Sodium Sulfate I. Introduction Caffeine is an alkaloid of the methylxanthine family. Its chemical

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    Investigation into How the Concentration of a Reactant Can Affect the Rate of Reaction Aim To plan an investigation that allows me to measure the effect of increasing the concentration of a reactant on the rate of reaction. With the results generated‚ it is also hoped to draw accurate conclusions and explain the results using scientific knowledge. Introduction Some reactions are fast‚ for example neutralisation or burning magnesium in air to produce magnesium oxide. However‚ other reactions

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    Extraction of caffeine from tea bags ABSTRACT Caffeine extraction from the commercial tea leaves (Lipton Yellow Label Tea) that was done is multiple extraction. 4 tea bags   were used in the experiment; tea leaves were weighed having 8.5333 grams. The leaves were boiled in a beaker with 150ml of water; the aqueous tea extract was transferred in a seperatory funnel mixed with DCM (20ml)‚ done thrice. The DCM layer was washed with 20ml 6M NaOH in the seperatory funnel; the organic layer was dried

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    Pulse Rate

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    Posture | Time (Minutes) | Pulse Rate(Beats/30 seconds) | Pulse Rate x2(Beats/minute) | Lying Down | 1 | 24 | 48 | Standing Up | 1 | 30 | 60 | Pulse Rate after 15 seconds of exercise (Beats/15 seconds) | Pulse Rate x6 in order to measure beats/minute(Beats/minute) | 11 | 66 | 3. Record how long this takes in seconds. - 38 seconds 4. Calculate the increase in the pulse rate immediately after the 15 seconds exercise compared with your standing rate. 66-60= 6. 6 pulses increased

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    percent of the caffeine molecule dissociates in water‚ proving that the compound is a weak electrolyte. A substance that completely dissociates in a solution‚ such as water‚ is considered an electrolyte and can therefore conduct electricity. This dissociation is caused by the atoms’ minimal nuclear charge‚ allowing the substance to break apart entirely into its ions. Ions are mobile‚ which induces a current and contributes to the substance’s high electrical conductivity. Caffeine is composed of atoms

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    "Explain the concept of homeostasis with reference to the control of heart rate‚ breathing rate‚ body temperature and blood glucose levels" P5 Homeostasis is where the body keeps a constant internal environment. This involves all the metabolic processes taking place In the body as well as the blood‚ tissue fluid and all the contents in the body ’s cells. There are a range of variables from heart rate to the blood glucose levels that the body will take into account. Negative feedback will occur

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    Heart Failure

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    the office at different times today‚ each with documented heart failure: one diastolic and the other systolic‚ and both are hypertensive. First‚ discuss the difference between systolic and diastolic heart failure‚ providing appropriate pathophysiology. ACEI/ARBs are the only medications prescribed for CHF that have been found to prolong life and improve the quality of that life. EXPLAIN the mechanism of action of ACEI/ARBs and how they affect morbidity and mortality in CHF. Be specific. Diuretics must

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    Investigating Factors that Affect the Rate of Reaction of the Decomposition of Hydrogen Peroxide Emilio Lanza Introduction- In this experiment‚ the rate of reaction‚ calculated in kPa sec-1‚ of the decomposition of hydrogen peroxide will be investigated to see how the change in concentration of hydrogen peroxide and the change in temperature affect the rate of reaction. The data will be collected by measuring the gas pressure. The product of Hydrogen Peroxide is oxygen in a gas state thus

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    Chemistry IA How does the molecular mass of alcohols affect its rate of evaporation? Introduction Alcohols are some of the most important molecules in organic chemistry. They can be converted into many different types of compounds. Alcohols contain the hydroxyl functional group (-OH)‚ bonded to a carbon atom of an alkyl or substituted alkyl group. The weight of the different compounds will differs because of the amount of hydrogen bonding. There are three kind of alcohols‚ primary‚ secondary

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    Caffeine Ruler Reaction Time Test * OBSERVATION/ASK QUESTION * INTRODUCTION/RESEARCH * HYPOTHESIS * EXPERIMENT/DATA * CONCLUSION Materials
 ·    Ruler ·    Paper
 ·    Pencil
 ·    Chart ::OBSERVATION:: Those drinking coffee appear to be more alert in class. Does drinking coffee improve mental and physical function? } } { { Can the effects of coffee alter coordination? ::HYPOTHESIS:: Caffeine improves your mental &

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