[Unit 1.8] | Factors Affecting Enzyme Action

Question 1

What is the effect of increasing the temperature of an enzyme?

Answer 1

• Initially, there will be more successful collisions due to an increase in kinetic energy so the rate would increase.
• At some point beyond reaching the optimum temperature, the enzyme will permanently denature: the shape of the active site would no longer complement the shape of the substrate and therefore it would not function.

Question 2

What is the effect of changing the pH of an enzyme.

Answer 2

It impacts the charges on the amino acids and deforms the shape, meaning ES complexes cannot form.

Question 3

How does increasing the enzyme concentration affect the rate of enzyme activity?

Answer 3

• While the substrates are in excess, adding more enzymes will increase the rate.
• When the substrates are no longer in excess, the rate will plateau and no longer increase.

Question 4

How does increasing the enzyme concentration affect the rate of enzyme activity?

Answer 4

• While the substrates are in excess, adding more enzymes will increase the rate.
• When the substrates are no longer in excess, the rate will plateau and no longer increase. The maximum number of ES complexes is reached.

Question 5

How does increasing the substrate concentration affect the rate of enzyme activity?

Answer 5

• While the enzymes are in excess, adding more substrates will increase the rate.
• When the enzymes are no longer in excess, the rate will plateau and no longer increase. The maximum number of ES complexes is reached.