Factors Affecting Enzyme Action

Question 1

How is the rate of an enzyme-controlled reaction measured?

Answer 1

1. The formation of the products of the reaction
2. The disappearance of the substrate

Question 1

How does temperature affect the rate of an enzyme controlled reaction?

Answer 1

-An increase in temperature increases the kinetic energy of molecules. This results in substrate molecules and enzymes colliding more often, leading to an increase in the rate of enzyme action.
-However after a certain temperature, the bonds within the enzyme begin to break down, and denaturation occurs, which is an irreversible process. This lowers the rate of reaction.

Question 2

How does rising pH affect the rate of an enzyme controlled reaction?

Answer 2

-A change in pH alters the charges on the amino acids that make up the active site of an enzyme. As a result, the substrate can no longer become attached to the active site, and so the e.s. complex cannot be formed.
-If there is a significant change in pH, the bonds maintaining the tertiary structure may break, changing the shape of the active site (Denaturation).

Question 3

How do substrate and enzyme concentration afffect the rate of an enzyme coontrolled-reaction?

Answer 3

-As enzyme concentration increases, the rate of reaction increases. This happens until there are more enzymes than substrate molecules, resulting in a plataeu.
-As substrate concentration increases, the rate of reaction increases. This happens until there is more substrate than enzymes, resulting a plataeu.