The aim of this experiment was to determine the effect of caffeine on resting body temperature. This has to do with homeostasis, which is the maintenance of equilibrium. In other words, it is a stable body state. Homeostasis refers to the process of keeping the internal body environment in a steady state, when the external environment is changed (Homeostasis 2). Humans are warm-blooded creatures that generate body heat internally and maintain body temperatures at a fairly constant level – about 98.6oF (Chiras 3). In this experiment, the effect of different amounts of caffeine on resting body temperature was examined.
Pure caffeine is a white powder, like what is found in caffeine pills, and is “a plant-based alkaloid which stimulates the central nervous system of any creature that ingests it” (Pollick). It is produced as a by-product of de-caffeinating coffee (Emsley 80). Caffeine is known chemically as 1, 3, 7-trimethyl-xanthine. It has xanthine as its core molecule, and attached to that are three methyl groups on atoms 1, 3, and 7. Caffeine is metabolised by the liver, which can take about 12 hours to remove 90% of any caffeine someone has consumed (80). Caffeine is a stimulant that increases the heart rate, blood flow, and respiratory rate, which in turn will increase body temperature.
The thermoregulatory centre in the hypothalamus controls body temperature. It receives input from two sets of thermoreceptors: receptors in the hypothalamus itself monitor the temperature of the blood as it passes through the brain, and receptors in the skin monitor the external temperature (Homeostasis). Body temperature varies throughout the day as it fluctuates within a range. The standard body temperature of a human is 98.6oF, but can differ as to what activities one is doing, or the time of day, for example if the sun is shining. To measure body temperature in this experiment, an oral thermometer was used, as it is one of the most effective ways of measuring body temperature.
Caffeine affects different people differently as some may or may not have a tolerance for it. In addition, caffeine will act differently in men and women of different heights and masses. This experiment was put forth upon a healthy 18-year-old female with low tolerance of caffeine who is approximately 63 kilograms. Doses of caffeine were administered every other day to avoid caffeine dependence. Each trial will be done three times to gain sufficient results. There will be trials of 50 mg, 100 mg, 150 mg, and 200 mg of caffeine. The control is the resting heart rate with no caffeine in the system. Once the doses of caffeine are administered, the test subject will sit in a quiet, blank room, for fifteen minutes. After fifteen minutes, the body temperature of the test subject will be taken using an oral thermometer. The body temperature of the test subject will rise as the doses of caffeine become stronger. The independent variable is the amount of caffeine, while the dependent variable is the body temperature measured. Hypothesis
If more caffeine is administered to the test subject, then the test subject’s body temperature will rise. Materials
30 caffeine pills (50 mg each, such as NoDoz, etc.)
A quiet room
A test subject
The caffeine pills and thermometer were gathered; a quiet room and a test subject were found. This experiment, and each trial, took place every second day so the body could rest and not become dependent on caffeine. 2.
The resting body temperature of the test subject, with no caffeine in their system, was taken and recorded before each trial. This remained a constant of 98.6oF. The body temperature in this experiment was measured orally with the thermometer. 3.
One caffeine pill (50 mg) was administered to the test subject. 4.
The test subject remained sitting in the quiet area for 15 minutes, which was recorded on the stopwatch. When the 15 minutes was up, the...
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