Practical B3 - Effect of temperature on the action of an enzyme
Procedure
Set up water baths at various temperatures (e.g. 0掳C, 20掳C, 40掳C, 60掳C and 80掳C).
Add starch solution to 5 test tubes.
Add amylaseAn enzyme that can break down starch into simple sugars. solution to another 5 test tubes.
Place one starch and one amylase test tube into each water bath for 5 minutes - to allow the enzymeProteins that act as biological catalysts, meaning they speed up reactions without being used up themselves. and substrateA substance on which enzymes act. to reach the desired temperature.
Place 1 drop of iodine into each dimple on a spotting tile.
Add the amylase to the starch in the 0掳C water bath.
Start the timer.
Every minute remove a sample of the starch-amylase solution and add it to a drop of iodine on the spotting tile.
Repeat step 8 until the iodine no longer changes colour - meaning that there is no starch present, in other words the amylase has broken all starch down.
Repeat steps 6-9 for each of the temperatures.
Record results.
Draw a graph to show the time taken for starch to be digested at different temperatures.