Physiology---Homeostasis Method/ References - Essay Example

Due Homeostasis Lab Report Methods Water Bath Experiment (Fox 3 A) This experiment aimed at determining whether negativefeedback plays crucial role in homeostatic mechanisms (Gordon, 1994). A water bath was set at 50º C, by first been turned on and allowed to come up to temperature. A thermometer was used to monitor temperature after the heater was shut off as it was indicated by the red light going off, and the temperatures below were recorded consecutively at an interval of one minute (ºC):49.7, 49.8, 49.8, 49.8, 49.

9After the temperatures were recorded, a large amount of ice water (8.1 ºC) was added to the water bath leading to a drastic drop in the temperature to 37.6 ºC (Laboratory Manual). This was followed by gradual rise in temperatures for 47 minutes to return to the set point (50 ºC) indicated by the shutting off of the heating light on the water bath (Laboratory Manual). The manual protocol was followed to do this experiment. Heart Rate Experiment (Fox 1.3 B)This experiment aimed at determining average personal heart rate as well as variability in the average heart rate an exercise and non-exercise group.

The personal heart rate was determined both in 15 seconds and 1 minute intervals in 5 trials for both (Laboratory Manual). However, group heart rate was determined on both exercise and non-exercise groups. The heart rate results from both groups were recorded in intervals of 90-99, 80-89, 70-79, 60-69 and 50-59. The manual protocol was followed to do this experiment.Acid-Base Buffer Experiment (Fox 8.4A)It is evident that buffers play a very important role in our bodies in the process of maintaining an acid-base balance (Goldstein and Kopin, 2007).

This section had two sections, that is, measuring the pH of water and buffer solution. There were slight deviations from the manual protocol in this experiment because the laboratory manual was unclear on exact procedures to be used in some sections and necessary controls were not evident in some sections. So some deviations were included as shown in the procedures below that were adopted for the two sections. Part One: Measuring the pH of WaterA beaker was first washed in soapy water while scrubbing the inside with a paper towel followed by proper rinsing.

50 ml of fresh water were placed in the beaker. The pH was measured (Laboratory Manual). One drop of HCl was then added into the beaker using a plastic disposable pipette. The water was swirled with the pH meter and the pH was measured when it stopped changing rapidly. Two more drops of HCl were added and the pH was again measured after it stopped changing rapidly (Laboratory Manual). Another beaker was obtained and the above procedure repeated using drops of NaOH rather than HCL. Part Two: Measuring the pH of 7.

0 Buffer SolutionA beaker was first washed in soapy water while scrubbing the inside with a paper towel followed by proper rinsing. 50 ml of the pH 7.0 buffer solution were placed in the beaker. The pH was measured. One drop of HCl was then added into the beaker using a plastic disposable pipette (Laboratory Manual). The pH 7.0 buffer solution was swirled with the pH meter and the pH was measured when it stopped changing rapidly. Two more drops of HCl were added and the pH was again measured after it stopped changing rapidly.

Another beaker was obtained and the above procedure repeated using drops of NaOH rather than HCL (Laboratory Manual). Exercise and Co2 Production Experiment (Fox 8.4 B)This experiment aimed at determining whether exercise increases Co2 production as a result of increased O2 consumption and hyperventilation (Marieb and Hoehn, 2007). Two largest beakers in the lab and a straw were obtained. Each of the beakers was first washed in soapy water while scrubbing the inside with a paper towel followed by proper rinsing (Laboratory Manual).

100 ml of fresh water were added into one beaker. 2 ml of 0.10 N NaOH were added into the water. Two drops of phenolphthalein were then added and the solution turned pink after mixing well with the straw. This solution was then divided equally into two beakers to ensure each beaker had 50 ml of the solution of the same concentration. Then a subject was allowed to blow through the straw at a steady rate into the solution in one beaker until it turned from pink to clear (Laboratory Manual). The time only taken by the subject exhaling through the straw was recorded, and not the total time.

Then subject was allowed to exercise and repeat previous step using the same rate of blowing into the solution and the time taken recorded. The manual protocol was followed to do this experiment.Hyperventilation and Co2 Production Experiment (Fox 8.4 C)This experiment aimed at determining whether there is a difference in respiratory rate (bpm) for individuals after normal breathing and after hyperventilation (Goldstein and Kopin, 2007). A subject resting breathing rate was measured by counting the number of breaths that they took in 30 seconds and the obtained number was multiplied by two (Laboratory Manual).

Close attention was paid because sometimes it is difficult to see the chest rise and fall. The number of breaths was recorded. The subject was allowed to hyperventilate and the resting breathing rate was measured by counting the number of breaths that they took in 30 seconds and the obtained number was multiplied by two. The final number is then recorded and close attention was also paid for precise determination of the number of chest rise and fall (Laboratory Manual). The manual protocol was followed to do this experiment.

ReferencesGoldstein, Davies S. and Kopin Ian J. “Evolution of concepts of stress”. Stress, 10.2 (2007): 109–120.Gordon, Charles J. “Thermoregulation in laboratory mammals and humans exposed to anticholinesterase agents”. Neurotoxicology Teratology, 16.5 (1994):427-53.Laboratory Manual, Laboratory 02 Experiment. Marieb, Elaine N. and Hoehn Katja. Human Anatomy & Physiology, 7th edition, San Francisco, CA: Pearson Benjamin Cummings, 2007.