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Biology Coursework: What Effect PH has on Enzyme Activity?

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Biology Coursework: What Effect PH has on Enzyme Activity? By James Patney 11U Enzymes are known as biological catalysts. They are widely used in today's world to alter or speed up the rate of reaction without themselves being changed. Enzymes are globular proteins which act as catalysts. A catalyst is a chemical substance, which speeds up the rate of reaction. For an example in the human body there are several thousands of chemical processes going and the quicker these happen the better it is, so enzymes are produced to increase the rate of reaction. Every biological process has it own enzyme especially designed for the process e.g. In the process of digestion salivary glands produce an enzyme called amylase in the saliva this enzyme starts the break down of starch. So enzymes are specific for one process. All enzymes work their best at an optimum PH or temperature. These means that for enzymes to work effectively they have to be in the right conditions. All enzymes have different optimum levels. So enzymes work best at a: * Particular level of acidity or alkalinity (PH) * Particular level of temperature ( oC) The graph below shows this: Enzymes can also become denatured. This means that enzymes will be destroyed if the conditions become too inappropriate. ...read more.


To make my results as a whole more accurate I shall do the experiments three times so then I know that if my results are similar then the evidence is more reliable because in the first experiment an error may have occurred. I will plot a mean value for the results I get. Safety When I am doing this experiment I must consider the safety issues that may arise to my attention. I have considered how I shall under go this experiment and therefore summed up the safety measures that should be in placed to prevent any injury or damage. These are: * Safety goggles must be worn to prevent splashes of any substances in the eyes * The environment should be made clear with surfaces clear, bags and coats and stools placed in relevant places * We should also be careful with the substances that will be used. Hydrogen peroxide is a corrosive substance so eye protection must be worn and concentrations of the substance must be kept low so there is not a harmful, extreme reaction. If substance is swallowed then the casualty's mouth should be washed out and he or she should be given a glass or two of water and if the liquid gets in eyes or skin the area affected should be flooded with water. ...read more.


Concerning my method there are a number of alterations or improvements I could have made to obtain more evidence to support my conclusion. As said I could have used further and more precise pHs of solutions. A problem that was encountered whilst doing the experiment was that when the froth would rise it would be a bit difficult to measure how much it had risen because if it overflowed from the measuring cylinder, measuring it was quite a hard procedure and not accurate. To ensure this would not happen I could have used bigger measuring cylinders and in case froth would spill I would cello tape a ruler around the cylinder. Also another problem that occurred was that noting the colour I get from the pH to diminish this problem I could have had sources of information which relate to the pH's and it's colours. Although my scientific knowledge enables me to recall the pH's to their corresponding colours textbook material would have been handy to check that the pH of each solution was correct. The experiment on the whole was a success, but it could be improved by the use of more accurate equipment and with me thinking more logically about minor implications that could occur. Resources Used For Research * CGP EDEXCEL Modular Science Revision Guide Book 1 Edited by Richard Parsons * LONGMAN revision guides GCSE/key stage 4 Biology by Martin Barker, Alan Jones and Chris Millican James Patney 11U Biology Coursework ...read more.

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