C5 Factors Affecting Enzyme Activity

Question 1

What are the six factors that affects enzyme activity?

Answer 1

Enzyme concentration
Substrate concentration
Temperature
pH
Cofactor
Inhibitor

Question 2

What happens if substrate concentration increases?

Answer 2

For increases until a maximum rate. Substrate concentration increases until reaches a maximum rate. Enzyme is fully filled and saturated.

Question 3

What happens when enzyme concentration increases?

Answer 3

Ror increases as more active sites are available so more substrates can bind.

Question 4

How does temperature increase rate of reaction?

Answer 4

When temperature increase, kinetic energy increases, which increases the collisions between substrates and active sites as molecules move more rapidly. Breaking of weak bonds occur. Above optimum temperature, enzyme denatured.

Question 5

What are cofactors?

Answer 5

Nonprotein molecule that is required for the proper functioning of enzyme often for processes that cannot be carried out by amino acids.

Question 6

Are cofactors organic or inorganic?

Answer 6

Both. Inorganic cofactors binds to permanently to the active site or loosely and reversibly at the substrate in ionic form. The organic cofactors are called coenzyme.

Question 7

What are inhibitors?

Answer 7

Substances which reduce, interfere or destroy enzyme activity. They prevent enzymes from catalyzing reactions. Resembles substrates.

Question 8

Inhibitors binds by what bonds?

Answer 8

Covalent bond - irreversible
Weak interaction - reversible

Question 9

What are the types of inhibitors?

Answer 9

Competitive (reversible) and non-competitive(non-reversible and reversible).

Question 10

How does competitive inhibitors affect the ror?

Answer 10

The inhibitor that resembles substrates binds to the active site of the enzyme instead of the substrate. Substrate can’t bind to the occupied active site. This reduces enzyme productivity.

Question 11

How can competitive inhibition be encountered?

Answer 11

Increase substrate concentration which increase likeability of substrate to bind to active site.

Question 12

Describe how does reversible non-competitive enzyme affect ror?

Answer 12

The structure of both substrate and inhibitor is different. Inhibitor bind to the allosteric site and changes the conformation of the enzyme. Cannot be overcame by adding substrates.

Question 13

How does irreversible non -competitive enzyme affect ror?

Answer 13

Binds at active site or other part of the enzyme by covalent bonds which just denatures the enzyme.