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Investigate the effect of temperature on the rate of reaction for the enzyme amylase.

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Planning Introduction Enzymes are found in the body and are used for the digestion of different food molecules. Amylase breaks down Starch to glucose while other enzymes break down other food molecules. Aim I am experimenting to investigate the effect of temperature on the rate of reaction for the enzyme amylase. Background Knowledge Some enzymes function best at 37oC, which is body temperature. This is a proven theory for the enzyme amylase. If the temperature is above or below 37oC these enzymes function slower, and therefore take more time to break down these food molecules. However, at very high temperatures enzymes change shape and no longer carry out their function, they are said to be denatured. This is why I am testing to see how temperature affects the rate of reaction in detail. Amylase is also known as carbohydrase as used in the diagram below. (Diagram from http://www.gcsescience.com) Variables Amount of Glucose Present. This is the dependent variable of my experiment I will test this using iodine to display if there is glucose present. I will test this after the amylase has had enough time to break down the starch. If the iodine should change black in the final solution, it means no reaction has taken place, but should it turn orange, a reaction has taken place. ...read more.


5 minutes 50oC 6 minutes 55oC 10 minutes 60oC No Reaction From the trial data it is clear to see the only variables that have an effect on the experiment are time and temperature. Obtaining Evidence Introduction These are my results I found out when I did my experiment. I repeated the experiment 3 times to ensure the best accuracy. Experiment 1 Temperature Time 25�C 05:00 30�C 03:00 35�C 01:30 40�C 02:00 45�C 03:00 50�C 03:40 55�C 04:00 60�C No Reaction Experiment 2 Temperature Time 25�C 02:00 30�C 01:45 35�C 01:20 40�C 02:00 45�C 02:40 50�C 03:00 55�C 03:20 60�C No Reaction Experiment 3 Temperature Time 25�C 03:30 30�C 02:40 35�C 01:00 40�C 02:00 45�C 03:20 50�C 04:00 55�C 04:40 60�C 05:20 Mean Averages Temperature Time 25�C 210 Seconds 30�C 165 Seconds 35�C 76 Seconds 40�C 120 Seconds 45�C 180 Seconds 50�C 213 Seconds 55�C 240 Seconds 60�C N/A Analysis Experiment 1 In this graph of experiment 1, the reaction time has a minimum value of 1:30 this happens at 35�C. The highest value occurs at 25�C and this is 5:00. From 25�C to the minimum value of 35�C the reaction time decreases at a decreasing rate. From the minimum value 35�C to the last value of 55�C the reaction time increases at a decreasing rate. ...read more.


Improvements The procedure used was simple and straightforward, however only one difficulty was encountered as mentioned before. This was the concentration of the amylase. A small improvement could have been made by testing the concentration of the amylase at the start before starting our experiment. Alternatively, our own concentrations of amylase could have been made up, as to ensure that the amylase was always the same concentration. We could of also have taken results at different temperatures to increase our range of results this would of helped dramatically to able us to a see a trend more clearly. More repeats could be taken but I don't think this would add much to the accuracy of the conclusions. More accurate equipment could have been used but again but I don't think this would add much to the accuracy of the conclusions. Extending the investigation Suggestions have already been made to extend the investigation to improve our knowledge of enzyme activity. After having previously found out about how temperature affects one particular enzyme, we could test other enzymes but according to my background knowledge most enzymes function at body temperature anyway. We could also test to see what the effects of PH have on enzyme activity and test to find out the optimum PH. Then we would have a full set of results to show the overall best conditions for enzyme activity. ...read more.

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