2. Aim: What factors affect the rate of enzyme activity? I. Factors that affect rate of Enzyme Activity A. The amount of substrate

3. 1. Increased amounts of substrate will speed up reactions when there are a lot of enzymes available for reactions. B. Temperature Optimum temperature

4. 1. In general, enzyme activity increases as temperature increases – to a certain point. a. Optimum temperature – the temperature at which enzyme activity works at its highest rate. Optimum temperature in humans is body temperature (98.6 o F or 37 o C) b. Enzyme Denaturation – when an enzyme loses its shape and its ability to carry out its proper chemical reactions due to high temperatures. In humans, this occurs at about 104 o F or 40 o C

5. C. pH – the measure of how acidic or basic something is.

6. 1. pH scale – 1-14. 1 is the strongest acid and 14 is the strongest base. 7 is neutral. 2. In general, enzymes work best at a pH of 7. Some enzymes work best at different pH levels dependent upon where they are working. Ex: the enzyme Pepsin in the stomach works best at a pH of 1-3.