What is the first step in investigating the effect of pH on enzyme activity?

The first step in investigating the effect of pH on enzyme activity typically involves preparing the necessary components of the experiment rather than measuring temperature or heating solutions. In this context, having a spot tile with iodine solution is essential for conducting the experiment involving amylase, as this enables you to test for the presence of starch.

When amylase breaks down starch into maltose, the iodine can be used to indicate when starch is no longer present by changing color. This color change will help in assessing the activity of the enzyme under different pH levels. Therefore, preparing a spot tile with iodine solution is a critical early action for successfully conducting the experiment and obtaining results regarding enzyme activity.

Measuring the temperature or heating water applies to preparing enzyme reactions generally but does not directly pertain to initiating the procedure for testing the effect of pH on enzyme activity specifically. Adding amylase and buffer is also part of the procedure but happens after the preparation step. Heating water to 100°C is generally not relevant for pH investigations involving enzymes, whose activity is often significant at physiological temperatures.