This lab will be driven by the research question, do changes in temperature (4oC, 25oC, 37oC, 50oC and 70oC) have an effect on the reaction rate of enzyme amylase and starch?
Hypothesis
As the temperature increases, the enzyme will have a quicker reaction time with the starch, therefore when met with the iodine, no change will occur in the colour of the solution, showing that the starch is now absent. The enzyme amylase and starch solution in 4oC and 25oC will change the colour of the iodine to a dark blue-black in the first few minutes, showing that the reaction hasn’t been completed, however for the 50oC and 70oC trials, the amylase and starch will create little to no change in the colour of the iodine when met almost immediately …show more content…
The trials range from almost melting point at 4oC (as a control) to 70oC. If the temperature is too low, there can be little to no noticeable reaction since the enzyme is operating below its optimal temperature, however if the temperature is well above the enzymes prime operating temperature, thermal deactivation or denaturation can occur (vlab.amrita.edu, 2012). This process modifies the molecular structure of a protein, it involves breaking weak links or bonds within a protein molecule that are responsible for the highly ordered structure of the protein in its native state. The consequence of this phenomenon is the loss of the catalytic ability of an enzyme, the enzyme is no longer a catalyst, so no reaction can occur. The denaturation of many proteins, including alpha and beta amylase is irreversible (Encyclopedia Britannica, …show more content…
Different amounts of solution may increase or decrease reaction rates. Changing amounts during the experiment will not make it a fair test. 1cm3 of amylase solution and 2cm3 of starch solution will be measured using a measuring cylinder into each test tube.
Temperature of the water bath. The temperature will affect the reaction rate of the enzyme amylase specifically. The temperature of the water bath will stay at its desired temperature for all 5 trials, a thermometer will be in the bath to ensure that the temperature remains constant.
Type of sugar in solution Different sugars may increase or decrease the rate of reaction between it and the amylase Starch will be used.
Time (minutes) If different trials last longer than others, or if the solutions are tested earlier or later than other trials, the experiment would not be a fair test. Each trial will last 3 minutes after the starch solution is poured into the amylase solution, using a pipette the solution will be taken every 30 seconds to be tested with the iodine
Size of test tubes The size or volume of test tubes may affect the reaction between the solutions All test tubes in this experiment will have the same length, diameter and size to maintain a constant