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Effect that the temperature has on the rate at which the Amylase (enzyme) can breakdown its starch (substrate)

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Effect that the temperature has on the rate at which the Amylase (enzyme) can breakdown its starch (substrate) Aim The aim of this experiment is to find out the effect that the temperature has on the rate at which the Amylase (enzyme) can breakdown its starch (substrate). Hypothesis I predict that the higher the temperature the higher the rate at which the enzyme breaks down its substrate would increase until it reaches the optimum point it will then decrease. For amylase the optimum is approximately 40?C. I know this because there are 2 types of amylase which are both found in the human body, the human body is at 37?C so that is why 40?C is the optimum. As temperature gets higher enzyme activity increases. This is because the movement of enzyme molecules and substrate molecules increases. This causes more collisions between enzyme and substrate and result in the formation of more products. Once the reaction reaches its optimum temperature it is important to maintain it otherwise you can denature the enzyme, which will result in a rapid decrease in enzyme activity. ...read more.


Shake the solution then place it in the colorimeter and record the absorbance by pressing the T button 7. Repeat steps, 4, 5, and 6 for each of the 10 concentrations of starch 8. Record results in a table see below (actual results) Tube Concentration of starch (%) Absorbance Absorbance Average absorbance 1 0.5 - 2 0.25 - 3 0.125 - 4 0.0625 - 5 0.03125 - 6 0.015625 - 7 0.0078125 - 8 0.00390625 - 9 0.001953125 - 10 0.0009765630 - 9. Repeat this entire experiment twice and calculate the averages. 10. Use the results to plot a graph of % absorbance against concentration of starch. 11. This graph can then be used to calculate concentrations of solutions if the absorbance is known, by drawing a line from the absorbance to the line of best fit then a line down to the concentration axis. Method The independent variable is temperature, as this is the factor I will be investigating. The dependant variable is rate of reaction. ...read more.


4. Start the digestion by mixing the two solutions in the test tubes with the glass rod while simultaneously starting the stopwatch. 5. As soon as you've mixed the starch and amylase take 1cm of the mixture and put it in one of the iodine tubes and shake. 6. Set the colorimeter to zero using the dilute iodine solution. 7. Check the absorbance of the solution and record it in a table. Time (minutes) Absorbance % Starch concentration 0 - 2 - - 4 - - 8. Repeat step 5,6,7 every two minutes 9. After ten minutes repeat the whole experiment. 10. Find the % starch concentration by using the calibration graph. 11. Plot a graph of starch concentration (%) against time (min) record the initial rate of reaction as follows. Temperature (oC) Initial rate of reaction (g per 100cm per minute) 10 0.03 20 0.05 12. Do the whole experiment at the various temperatures between 10-80 degrees Carry out this entire procedure at the various temperatures 10,20,30,40,50,60,70,80 degrees Celsius Risk assessment 1. Must wear safety goggles when using high temperature. 2. Be careful whilst handling glass objects 3. Do not get chemicals on skin can wear rubber gloves. ...read more.

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