The temperature will affect the rate of the reaction between the enzyme and the substrate. This is because when the temperature increases, the particles have more chance of a successful reaction as they have more energy and move around quicker. However when the temperature exceeds the optimum temperature the enzyme becomes denatured which means a reaction cannot take place.
Apparatus:
Here is a list of apparatus that will be used for this experiment:
6 test tubes
to hold the film and the substrate in
Water baths
to make the substrate the right temperature in order to carry out the experiment.
Stopwatch:
To time the time in which the enzyme reacts with the tape and removes the gelatin and photosensitive chemical layer.
Thermometer:
To make sure each water bath is at the correct temperature
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The Enzyme Trypsin
Concentrations of the enzyme (0.1% & 0.5%) will be needed for this experiment.
Variables
In order for the experiment to be successful, some things need to be kept the same and some need to be changed. The method has to be kept the same and the concentration of the enzyme also will be kept the same. Other things that wont change are the temperature range and PH of the enzyme.
Things that have to be changed to find the required results are the temperature and concentrations of the water and trypsin.
Step By Step Plan
- Put 5cm³ of the enzyme into a test tube
- Place test tube and enzyme in water bath, and make sure the bath is at the correct temperature so that the experiment is accurate.
- Put the film into the test tube.
- Start the stopwatch when the reaction starts which should be when the film is in contact with the substance inside the test tube.
- Stop stopwatch when the reaction is clearly complete.
- Note down reaction time results into a table.
- Repeat the above steps for each temperature twice so that the experiment is accurate.
TRIAL RUN
In order to make sure that the main experiment was carried out correctly a trial run was required.
A trial run gives you the opportunity to check if you are doing everything right and see if any improvements could be made on the final experiment.
Range
The approximate range of the temperatures for the trial run will be:
18°c
35°c
50°c
70°c
And The range of concentration will be:
0.1%
and 0.5% which will be tested to see which gives ideal times
Here are the results from the trial run:
After completing the trial run and looking at the results found I am not totally satisfied with the way the trial run had gone and the methods used to collect results.
A lot of things were carried out inaccurately. For a start we did not correctly note down the temperatures of the water baths or attempt to correct the temperatures in them. In the trial run you had to keep a good eye on the reactions otherwise you wont see exactly when the reaction started or stopped. I think a lot of the time we were just starting when the tape was placed in the substance and that is incorrect and inaccurate because it was important for the solution in the test tube to equilibrate to the correct temperature. This mistake would have effected the outcome of the reaction because the time would have been recorded as much longer than the actual reaction time should have been.
From the trial run we decided what ranges of concentration and temperature to use in the final experiment. We decide to use the 0.5 concentration because we found that the times recorded from the trial run with that concentration where not too short nor too long. The range of temperatures will be between 12°c and 70°c
Things to change for Final Experiment:
Thermometers – Will be used in order to measure the temperature of the solution before starting the stopwatch to find the reaction time. This is very important because if the temperature isn’t measured correctly the time recorded for that reaction would most probably be most accurate and the times wont be normal.
Stopwatches – Stopwatches are important in recording the reacion time and the stopwatches in the trial run weren’t entirely satisfactory, once the stopwatch reached a certain time it would stop.
Analysing
Above is a table with my individual results from the final experiment
Class Results
Above is the results collected from the class and the average time between them all. Most of the results where close together but some flaws in the method effected the reaction times.
Evaluation
After the final experiment has been completed and the results recorded I am moderately satisfied with the experiment. There was a lot of space for improvement both method and apparatus wise. I think that the results would have been a lot more accurate if we had had more time to complete the experiments and record the results. The accuracy in the final experiment was a lot better than the accuracy during the trial run. The trial run helped us to stop and think of what needed to be changed or what needed to be kept in order to find out how to correctly carry out the final experiment with as accurately as possible.
One thing that was a big problem was the temperature of the water baths which weren’t very reliable and proved a problem keeping them the right temperature. During the experiment the reactions should have been tested between 2-3 times to get a better range of results and to show clearly that the results are accurate.
