Factors Affecting Enzyme Activity

Question 1

What are the factors affecting enzyme activity?

Answer 1

1. Enzyme concentration
2. Substrate concentration
3. Temperature
4. pH

Question 2

How does enzyme concentration affect enzyme activity?

Answer 2

1. Increase in active sites of enzymes
2. Increase in successful collisions
3. Increase in enzyme substrate complexes
4. Increase in rate of reaction

Question 3

How does Low substrate concentration affect enzyme activity?

Answer 3

1. Active sites rarely come into contact with substrate
2. Active sites not all occupied
3. Fewer enzyme substrate complexes formed
4. Lowers rate of reaction

Question 4

What affect does an increasing substrate concentration have on enzyme activity?

Answer 4

1. More active sites come into contact with substrates
2. More enzyme substrate complexes formed
3. Increasing rate of reaction

Question 5

What affect does a high substrate concentration have on enzyme activity?

Answer 5

1. Active sites full of substrate
2. Substrates have to wait until enzyme substrate complex has dissociated into products and free enzyme before another reaction occurs
3. No effect on the enzyme activity

Question 6

How does low temperature affect enzyme activity?

Answer 6

1. Slow rate of reaction
2. Less kinetic energy
3. Less successful collisions between molecules, enzymes active site and substrate
4. Binding rare and less enzyme substrate complexes form

Question 7

How does increasing temperature affect the enzyme activity?

Answer 7

1. Increased rate of reaction
2. Kinetic energy increases
3. Substrate and enzyme molecules move faster
4. Increased successful collisions between active site and substrate
5. More enzyme substrate complexes form

Question 8

For every 10 degrees Celsius increased…

Answer 8

…rate of reaction doubles

Question 9

How does optimum temperature affect the enzymes activity?

Answer 9

1. Many successful collisions
2. Many enzyme substrate complexes form
3. Strain put on substrate molecule and distorts bond and lowers activation energy

Question 10

What is the affect of a temperature that is too high on enzyme activity?

Answer 10

1. Rate of reaction slows
2. Causes enzymes to denature
3. Vibrates so energetically that hydrogen and hydrophobic interactions begin to break (tertiary structure unravels)
4. Shape of active site altered and substrate no longer fits
5. Few enzyme substrate complexes

Question 11

What is the affect of extreme temperature in enzyme activity?

Answer 11

1. Eventually, all enzymes become denatured
2. Reaction stops

Question 12

What does it mean when an enzyme denatures?

Answer 12

When an enzyme has lost its tertiary, 3D structure

Question 13

How does change in ph affect the structure of enzymes?

Answer 13

Affects the 3D arrangement of enzyme

Question 14

How does change in ph affect enzyme shape specifically?

Answer 14

1. Affects ionic and hydrogen bond that retains 3D shape
2. Affects R group in active site with temporary which temporarily bonds with substrate

Question 15

What does a small ph change cause?

Answer 15

1. Inactivation of enzyme; reversible

Question 16

What does a big enzyme pH change cause?

Answer 16

Causes enzyme to become denatured

Question 17

What are the 2 types of inhibition of enzymes?

Answer 17

Competitive and non competitive

Question 18

Explain competitive inhibitors

Answer 18

1. competes with substrate for active site (active site directed)

Question 19

Explain non competitive inhibitors

Answer 19

1. Binds to another part of the enzyme (non active site directed) changing its shape so the active site’s shape is distorted and can’t bind to substrate

Question 20

Enzyme inhibitors may be…

Answer 20

…permanent or reversible

Question 21

What bond is permanent enzyme inhibitors?

Answer 21

Covalent

Question 22

What bond is reversible enzyme inhibitors?

Answer 22

Hydrogen bond

Question 23

What are the 3 examples of enzyme inhibitors?

Answer 23

1. Malathion
2. Penicillin
3. Cyanide

Question 24

What does malathion do?

Answer 24

Inhibits nervous system

Question 25

What does penicillin do?

Answer 25

Inhibits cell wall formation in bacterial cells so can’t reproduce

Question 26

What does cyanide do?

Answer 26

Blocks an essential enzyme

Question 27

What is an enzyme inhibitors?

Answer 27

A molecule that binds to the enzyme and blocks the activity