1. FACTORS AFFECTING ENZYME ACTIVITY

2.  There is an optimum temperature at which enzymes function best – generally around 40 degrees  But why the gradual build and drop off? TEMPERATURE

3.  Normal body temp is around 37 degrees  Above that temperature and the proteins that make up the enzyme begin to denature i.e. break down  Below that temp and the molecules are not moving at an optimum speed for the reaction to take place! TEMPERATURE

4.  pH (or the scale of acidity) also has a bell shaped curve  In highly acidic or basic environments enzymes do not function as well PH

5.  The optimum pH is around 8  Any more basic or acidic and enzymes can be broken down or denatured and begin to loose their function. PH

6.  The substrate (in our lab the H2O2) can vary within the body/cell based on a number of conditions  This will cause an increase in enzyme activity…. To a point! SUBSTRATE CONCENTRATION

7.  At some point, which will vary based on the other factors, the rate of reaction will not increase any further.  All of the enzymes are saturated or being used. SUBSTRATE CONCENTRATION

8.  As the enzyme concentration increases the rate of reaction increases.  This is true provided there are enough substrate molecules to continue to react with. ENZYME CONCENTRATION

9.  For instance, if there was always enough peroxide to react with, adding more catalase would increase the rate of reaction indefinitely ENZYME CONCENTATION