Enzymes

Question 1

What are enzymes

Answer 1

Organic catalyst

Question 2

What type of protein are enzymes

Answer 2

Globular proteins

Question 3

How to enzymes speed up reactions

Answer 3

Enzymes lower activation

Question 4

How do enzymes lower activation energy

Answer 4

Temporary bonds form between the substrate molecule and amino acid on the surface of the active site

Question 5

Describe the induced fit model

Answer 5

• Active site changes shape as the substrate molecule approaches
• Substrate starts to form bonds with amino acid in the active site
• tertiary structure of enzyme adjusts so that the active site moulds itself tightly around the substrate
• change in the tertiary structure = active site fits perfectly to the substrate

Question 6

How are enzymes affected when the temperature increase to opt

Answer 6

• increases kinetic energy of the enzymes and the substrate
• increased collisions between enzymes and substrate
• reduction in the activation energy of the reaction
• increased production of E-S complexes

Question 7

How are enzymes affected when temperature increases above optimum

Answer 7

• hydrogen and iconic bonds break
• tertiary structure is lost
• active site changes shape
• fewer E-S complexes form

Question 8

What happens when it becomes to hot

Answer 8

Enzymes become desaturated as tertiary structure is lost forever

Question 9

how does low PH affect enzymes

Answer 9

• ionic and hydrogen bonds are Brocken

- enzymes denature

Question 10

How does a high PH affect enzymes

Answer 10

Ionic and hydrogen bond Brocken

Enzymes becomes denatured

Question 11

How are enzymes affected by substrate concentration

Answer 11

• firstly substrate concentration is limiting so more substrate is added so it can bind to free enzyme active site
• now enzyme concentration is limiting the rate of reaction as more substrate added it can not bind to enzyme active site as the are already bound substrate

Question 12

How are enzymes affected by enzyme concentration

Answer 12

• firstly enzymes concentration limiting rate of reaction as more enzymes addd it can bind to more substrate molecules
• however the substrate concentration is limiting the rate of reaction as more enzymes added it cannot bind to anymore substrate molecules as there are not enough substrate molecules

Question 13

Define competitive inhibitor

Answer 13

Are molecules that have similar shapes to the substrate

Question 14

Describe and explain competitive inhibitors

Answer 14

• The inhibitor competes with substrate for active site

- inhibitor are not permanently bound to the active site

Question 15

What happens when the inhibitor has a high concentration

Answer 15

It takes longer for the substrate to occupy the active site

Question 16

Describe non competitive inhibitors

Answer 16

The inhibitor attaches itslef to a binding site not the active site
After attaching t the enzyme and it changes enzymes shape and therefor change the shape of teh active site
So therefore the enzyme cannot form E-S complexes
Rate of reaction is reduced

Question 17

Describe the lock and key theory

Answer 17

Substrate attaches to the Active site

E-s complexes form