Enzymes

Question 1

What is the definition of an enzyme

Answer 1

A biological catalyst

Question 2

What do catalysts do

Answer 2

They increase the rate of reaction without being used up

Question 3

How do enzymes increase the rate of reaction

Answer 3

They do this by decreasing the amount of activation energy that is required for a reaction to take place, so more molecules have the activation energy or more allowing them to react.

Question 4

What is an example of an intracellular enzyme and what does it do

Answer 4

Catalase binds to H2O2 also known as hydrogen peroxide and catalyses it’s breakdown into water and oxygen

Question 5

What is an example of an extracellular enzyme

Answer 5

Amylase which is produced in the pancreas and released into the small intestine, catalysing the breakdown of starch into glucose.

Question 6

What is the molecule that binds to the enzyme called

Answer 6

It is called the substrate molecule

Question 7

What are the molecules that are produced called

Answer 7

The products

Question 8

What is the active site

Answer 8

The active site is where the substrate binds to

Question 9

When the enzyme binds to the substrate what is it called

Answer 9

An enzyme substrate complex

Question 10

What is the substrate in relationship to the active site

Answer 10

The active site is complementary to the substrate

Question 11

What does the complementary nature mean

Answer 11

Each enzyme is specific to the substrate ion binds to

Question 12

What happens once the substrate binds to the active site

Answer 12

Amino acids on the active site can form temporary bonds with the substrate ion

Question 13

What happens to molecules that aren’t complementary

Answer 13

It will not be able to bind to the active site

Question 14

What happens once the reaction is catalysed

Answer 14

A product complex is formed and then the product is released from the active site

Question 15

What are catabolic enzymes

Answer 15

enzymes that can break down larger molecules into smaller molecules

Question 16

What are anabolic enzymes

Answer 16

Enzymes that can build up larger molecules from smaller molecules

Question 17

What is the lock and key model

Answer 17

The substrate molecule fits perfectly into the active site similar to how a key fits into a lock. Furthermore, only one key can fit into the lock demonstrating the highly specific nature of enzymes.

Question 18

What is the induced fit model

Answer 18

The tertiary structure of the active site changes as the substrate approaches. As the substrate starts to form bonds with the active site, the active site undergoes a conformational change so that the active site moulds around the substrate. The conformational change allows the active site to perfectly fit the substrate

Question 19

How does the induced fit model show enzyme specificity

Answer 19

Molecules that aren’t the substrate can;t form the correct bonds to the correct amino acids in the active site. So the structure of the enzyme doesn’t adjust to fit the molecule.