Enzymes

Question 1

State the function of an enzyme

Answer 1

Biological Catalyst

Question 2

Give the term for a building up reaction

Answer 2

Anabolic

Question 3

Give the term for breaking down reactions

Answer 3

Catatonic

Question 4

Define metabolism

Answer 4

The sum of all different chemical reactions.

Question 5

Give the three factors that affect enzymes

Answer 5

pH
Temperature
Pressure

Question 6

What is the maximum rate an enzyme can catalyse called?

Answer 6

Vmax (maximum initial velocity)

Question 7

What do enzymes need in order to function?

Answer 7

Activation energy

Question 8

What does a catalyst do?

Answer 8

Increase the rate of successful collisions of molecules

Question 9

Name and describe the two key hypothesis of enzymes

Answer 9

Induced fit theory- enzyme slight changes shape to fit with substrate
Locke and key theory- enzyme fits perfectly with substrate

Question 10

Where does the substrate bind?

Answer 10

The active site

Question 11

What is it called when an enzyme attaches to the substrate?

Answer 11

An enzyme-substrate complex

Question 12

What is an enzyme that acts within a cell called?

Answer 12

Intracellular enzyme

Question 13

Give an example of an intracellular enzyme

Answer 13

Catalase- breaks down hydrogen peroxide to water and oxygen

Question 14

What is an enzyme that are released from cells to act outside a cell called?

Answer 14

An extracellular enzyme

Question 15

What is the purpose of extracellular enzymes?

Answer 15

To break down large polymers to make them able to move into the cell.

Question 16

Describe the digestion of starch

Answer 16

1. Starch polymers are broken down into maltose by amylase.
2. Maltose is broken down into glucose by maltase, present in the small intestine

Question 17

Describe the digestion of proteins

Answer 17

A protease called trypsin digests proteins into smaller polypeptides, and is broken down by other enzymes into amino acids

Question 18

Describe denaturation.

Answer 18

The tertiary bonds are affected, changing the shape of the enzyme and meaning it can no longer fit to it’s substrate, slowing the rate of catalysation.

Question 19

How can substrate and enzyme concentration effect the rate of reaction?

Answer 19

Affceted by Vmax

Question 20

Define an inhibitor

Answer 20

Molecules that prevent an enzyme from carrying out their normal function

Question 21

Name the two types of inhibition

Answer 21

Competitive and non competitive inhibition

Question 22

Describe the process of competitive inhibitors

Answer 22

The inhibitor binds to the active site and block the substrate, decreasing enzyme availability and the rate of reaction

Question 23

Describe the process of non competitive inhibitors

Answer 23

The inhibitor bind to the allosteric site, changing the tertiary structure of the protein and preventing the substrate from being able to bind to the active site, decreasing enzyme availability and the rate of reaction

Question 24

Give an example of competitive inhibition

Answer 24

Statins- drugs that inhibit an enzyme aiding in the synthesis of cholesterol

Question 25

Name the site that a substrate does not bind to.

Answer 25

Allosteric site

Question 26

What is end-
product inhibition?

Answer 26

When the product of a reaction acts as the inhibitor to the enzyme producing it.

Question 27

What is the difference between a cofactor and a coenzyme?

Answer 27

A coenzyme is organic, a cofactor is not.

Question 28

What is the purpose of a cofactor?

Answer 28

A non-protein component that helps the enzyme carry out it’s function.

Question 29

Give an example of a cofactor

Answer 29

Amylase uses a chloride ion in the breakdown of starch

Question 30

Give an example of a coenzyme

Answer 30

NADP uses vitamin B3

Question 31

Describe precursor action.

Answer 31

Many enzymes are produced in an inactive form, and undergo a tertiary change to be actiavted. A precursor enzyme is called an apoenzyme.