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Effect of a Factor on the Activity of an Enzyme

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Effect of a factor on the activity of an enzyme
Research Question:
How does pH effect the activity of the enzyme amylase and the hydrolysis of starch?
Amylase is an enzyme that acts on starch. pH is capable of altering the structure of the active site centre in the enzyme leading to denaturation. At each pH, the enzyme activity would be relatively different. Ideally the optimum pH is 6.0 when the enzyme works best and the fastest, however if the pH is higher or lower the hydrolysis of starch will be slower. Changing the pH above the optimum will sometimes lead to denaturation of the enzyme and the change in shape of the active site. (
Independent: The pH of the buffer solution.
Dependent: The time taken for the solution to turn an opaque (lighter) blue from dark blue.
Controlled: The volume of iodine solution; the volume of starch solution; the volume of buffer solutions; the volume of amylase solution; the temperature at 40°c; the time it is left in the water bath; and the concentration of the solutions.
I will be using a water bath to keep the temperature constant, and to manipulate my independent variable, I will be using pH 4, 5, 7, 9, 10 by adding different pH buffer solutions with the amylase. * 50ml Amylase solution * 100ml Starch solution * 100ml Buffer solutions with pH 4, 5, 7, 9, 10 * 20ml Iodine solution

Apparatus: * Test tubes x15 * Test tube racks * Boiling tubes x15 * Water bath * 50ml Burette ±0.1 * Pipette (dropper) * Stopwatch x5
1. Prepare a water bath at 40°c. 2. Prepare 5 test tubes and label them according to the range of pH. 3. In each of these test tubes, add in 2ml of amylase solution and 5ml of the buffer solution. Do this using a burette. 4....

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