Human Physiology ISA – ISA 1 Amylase Action

Enzyme Reactions

Variables Independent Dependent Control Variables Temperature Time it takes to digest starch Control Variables Volume of starch/iodine/water/amylase Concentration of starch/amylase

Apparatus 1% amylase 0.5% starch Strong iodine Thermometers Spotting tiles Tin foil Pipettes

Investigation- Independent Variable – Temperature Investigation- Independent Variable – Temperature. Dependent Variable- time taken for starch to digest To one test tube add 4cm3 of starch solution To another test tubes add 1cm3 of amylase Set up a water bath to your required temperature (20,30,40,50,60) Place both test tubes in the water bath for 5 minutes. During the 5 minutes set up a white tile with a drop of iodine in each well – each well represents 30 seconds. After 5 minutes pour the starch in to the amylase test tube. Start timing Take a small sample and place in the first well Place back in the water bath Take a sample from the test tube every 30 seconds and add to an iodine drop in the well. Continue until the colour no longer changes Repeat for different temperatures e

Results – Plot a graph Temperature © Time taken to digest starch (s) 20 210 25 150 30 90 35 40 45 180 50 330 55 600

Investigation What was the Control Investigation and why? Reliability Conclusion – include figures

Design an Investigation Think about variables Think about what you are changing – the temperature Think about what you need to keep the same Think about how you will know which one has worked Think about repeats