Enzymes - How fast a substrate disappears

The enzyme amylase catalyses the breakdown of starch to maltose. 

It's easy to detect starch using iodine solution - if starch is present, the iodine solution will change from browny-orange to blue-black. 

Set up th apparatus. Put a drop of iodine solution into each well on the spotting tile. Every 10 seconds, drop a sample of the mixture into a well using a pipette. When the iodine solution remains browny-orange (i.e. starch is no longer present) record the total time taken. 

Repeat with the water bath at different temperatures to see how it affects the time taken for the starch to be broken down. Remember to control all of the variables each time. 

You could improve the accuracy of this experiment by using a colorimeter - a piece of electronic equipment that measures the strength of a coloured solution so measurements aren't just based on somebody's judgement of when the colour has changed.