1.4 Proteins: Enzymes

Question 1

What is the role of an enzyme?

Answer 1

Reduces the activation energy to catalyse a chemical reaction

Question 2

What biological molecule is an enzyme?

Answer 2

Protein

Question 3

What are the monomers of an enzyme?

Answer 3

Amino acids

Question 4

What test can be done for proteins?

Answer 4

Biurets test

Question 5

What is a positive result for the Bieurets test?

Answer 5

Blue -> Lilac

Question 6

What is the induced fit model?

Answer 6

Substrate and active site similar but not complementary
When substrate enters active site, it changes the shape of the active site slightly to make it complementary
Puts pressure/tension/breaks bonds within the substrate
Lowers the activation energy of the reaction

Question 7

What is required for a reactions activation energy to be reduced?

Answer 7

Constant movement of both enzyme and substrate

Question 8

Describe the effect of increasing temperature on enzyme activity.

Answer 8

Increases up to the optimum and then decreases

Question 9

Explain how temperature effects enzyme activity.

Answer 9

More kinetic energy means more successful collisons and more ES complexes
After optimum, enzyme active site begins to denature

Question 10

Describe the effect of pH on enzyme activity.

Answer 10

Each enzyme has its own optimum pH
Enzymes denature too far from optimum

Question 11

How does increasing enzyme concentration affect rate of reaction?

Answer 11

As concentration increases so does the rate of reaction
More active sites are available
Same amount of products are made as there is the same amount of substrate