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Acid based write-up

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Acid based write-up Introduction: The pH of blood plasma needs to be regulated. This is because enzymes are present in the blood. Enzymes are globular proteins and are sensitive to pH. A significant change in pH would cause the enzymes to denature and enzymic reactions would cease. The pH of blood plasma is in the region of 7.4, while the pH within the cells is much lower then in the plasma, of the order of pH 6.1. This is because the H+ is made within the cells and this means a high concentration of H+, hence a lower pH (more acidic pH). Hydrogen ions in the blood plasma are dependent on two components: 1). The respiratory component and 2). The metabolic component. The respiratory component is the amount of CO2 present in the plasma. The metabolic component is the organic acids e.g. lactic acid and ketone bodies present. The CO2 factor is mediated by the lungs, while the organic acid and ketone body factor is mediated by the kidneys. The lungs and kidneys independently mediate the factors and so compensate for one another. This is important in for example respiratory depression (CO2 accumulation), when not enough CO2 is removed via the lungs. ...read more.


Peprin, an anti-coagulant is combined with the blood and thoroughly mixed by stirring with a magnet. The blood sample is also not exposed to air; otherwise the CO2 present within the blood will be lost to the atmospheric air. The blood samples taken are arterial samples. Venepuncture blood samples are taken from are vein. Veins carry deoxygenated blood i.e. it is low in oxygen and high in Carbon dioxide. Blood from arteries is oxygenated so the reverse is true. Thus taking Venepuncture blood samples will give different results. During hyperventilation one is breathing at an abnormally rapid rate at rest. Demands for Oxygen delivery and Carbon dioxide delivery are exceeded. This causes a reduction in Carbon dioxide concentration of arterial blood and an increase in oxygen concentration. This leads to a drop in blood pressure and proceeds to the subject feeling dizziness and a tingling sensation in the limbs. During exercise the muscles need an increased blood supply so that oxygen and glucose can be provided for aerobic respiration and waste carbon dioxide and heat can be removed. If the demand for oxygen by the muscles exceeds the amount of oxygen delivered via the lungs, anaerobic respiration occurs. ...read more.


Conclusion: Any activity involving the body causes a shift in pH from the mean value. This results in either acidosis or alkalosis. The body tries to correct this via its buffers, which act as to bring the pH back to the mean value. The kidney and the respiratory system reply correspondingly. If the pH exceeds the mean value to such an extent that the buffers cannot compensate by inducing equilibrium and so ultimately death is apparent. This has to be avoided at all costs. Evaluation: In the experiment only one subject was tested for each procedure. This is not statistically significant. In order to be statistically accurate a larger number of subjects should be tested, around the order of a 100, so that percentages can be drawn from this and a mean value can be determined. The exercise should be carried out for a longer period of time, for example twenty minutes, so it is visually obvious the breathing rate of the subject has increased; suggesting the body muscles are active. Three minutes are not enough to achieve this. This is because different subjects have different levels of fitness so require different minimum amounts of exercise for the above to be achieved. Twenty minutes would encompass even the fittest individuals. ...read more.

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