Enzymes: Special ProteinsEnzymes: Special Proteins
SWBAT•Determine the functions of enzymes•Determine enzyme regulation •Determine the effect of temperature, pH, and enzyme/substrate concentration on enzyme activity
Properties of Enzymes Properties
They are proteins
Highly specific
Have active site
Reused/ remains unchanged
LOWERS ACTIVATION ENERGY!!! Energy required to start a
chemical reaction
Enzymes are recycled and reused manytimes for the same type of reaction (never used up) Example: Sucrase converts sucrose glucose + fructose
Sucrase remains unchanged
Factors that affect enzymes
Factors that affect the strength of an enzyme: pH Temperature Concentration of
enzymes Concentration of
Substrate
Temperature Temperature
Each enzyme has an optimum temperature in which it works the best
Also a range of temperature in which it will work When the temperature drops/cools, activity of
enzyme decreases/slows down When temperature increases
1. Rate of reaction increases2. Then decreases3. Then stops (Denature)
Most Biological Enzymes work in a temperature of 37°C
pH
Most of biological enzymes work in a pH of 7, but there are some exceptions (Pepsin and Trypsin)
Enzymes are affected by pH and have an optimum pH
If the pH goes above or beyond the range, the enzyme becomes denatured
Concentration of Substrate and Enzymes The rate of reaction of the enzyme can
be increased by increasing the concentration of the enzyme
After a while the rate of reaction becomes constant
At this point , the rate of the reaction can be increased only by increasing the concentration of the substrate