Factors Affecting Enzyme Activity

Question 1

What are the factors affecting enzyme activity

Answer 1

Temperature
Ph
Enzyme conc
Substrate conc
Concentration of inhibitor

Question 2

How does enzyme concentration affect rate of enzyme activity

Answer 2

As conc is increased, more ES complexes are formed, increasing the rate of enzyme activity

Question 3

How does substrate concentration affect rate of enzyme activity

Answer 3

Increasing substrate conc means more ES complexes are made so the rate of EA increases

Question 4

What happens when a graph plateaus on a substrate concentration-rate graph

Answer 4

All the ES complexes have been made, so there are no more active sites

Question 5

How does concentration of inhibitor affect rate of enzyme activity

Answer 5

Increasing concentration means fewer ES complexes are made, decreasing the rate of enzyme activity

Question 6

How does pH affect rate of enzyme activity

Answer 6

If pH is too low or too high the enzyme denatures, so fewer ES complexes are formed decreasing the rate of enzyme activity

Question 7

How does temperature affect rate of enzyme activity

Answer 7

Too low = not enough kinetic energy so decreased rate
If you increase the temp, enzyme activity increases
Too high = enzyme denatures so there is fewer ES complexes, decreasing the rate of

Question 8

Where does a competitive fall on a inhibitor concentration-rate graph

Answer 8

Goes as high of a rate as no inhibitor, but takes longer to reach that point

Question 9

Where does a non competitive fall on a inhibitor concentration-rate graph

Answer 9

Doesn’t reach as high of a rate as competitive or no inhibitor does

Question 10

Where does a no inhibitor fall on a inhibitor concentration-rate graph

Answer 10

Reaches as high of a rate as a competitive inhibitor would, but gets to that point faster

Question 11

Why does a higher concentration of competitive inhibitors mean that ES complexes can’t form

Answer 11

Because they binds to and block the active site so substrates can’t bond

Question 12

Why does a higher concentration of non competitive inhibitors mean that ES complexes can’t form

Answer 12

They bind to the allosteric site and change the tertiary structure/shape of the active site so the substrate is no longer complementary so they can’t bind

Question 13

How can you reduce the effect of competitive inhibitors

Answer 13

Increase the concentration of substrate

Question 14

Can you reduce the effect of non competitive inhibitors? Why?

Answer 14

No, the change to the active site is permanent so it doesn’t matter whether or not the substrate concentration is increased as they can’t bind anyway

Question 15

What happens when enzymes denature

Answer 15

Hydrogen and ionic bonds break down