Enzymes

Question 0

Give examples of enzymes

Answer 0

Catalase
Amylase
Pepsin
Sucrase
Chymotrypsin
Trypsin

Question 1

What is the role of enzymes

Answer 1

They speed up chemical reactions,

Enzymes catalyze chemical reactions

Question 2

What are enzymes made up of?

Answer 2

• they are made from amino acids and ENZYMES are proteins
• when an enzyme is formed, it is made by stringing together of 100 and 1000 amino acids in a very SPECIFIC and UNIQUE order.
• the chain of the amino acids then folds into a unique shape
  That particular shape allows the enzyme to carry specific chemical reactions.

Question 3

How do enzymes speed up the rate of reaction?

Answer 3

They are biological catalysts, they speed up the rate of reaction by LOWERING the ACTIVATION ENERGY

Question 4

Do they change shape?

Answer 4

They remain unchanged until the end of the reaction

Question 5

Can enzymes be used up?

Answer 5

Enzymes are not used up in a reaction but can be reused, so only a small amount of enzyme is required for a reaction to take place.

Question 6

Definition of enzymes

Answer 6

Enzymes are organic catalysts produced by a living organism that brings about a specific biochemical reaction.

Question 7

Can enzymes be used for different reactants? Why not?

Answer 7

• enzymes are very specific and generally interact with one type of reactant (substrate) or pair of reactants. They form an enzyme substrate complex with the reactants.
• The arrangement of the amino acids in a protein gives it a very specific 3D shape.

Question 8

What is a substrate

Answer 8

The compound an enzyme acts on

Question 9

When an enzyme binds to the substrate, what is it called?

Answer 9

Enzyme substrate complex

Question 10

What are the two models of enzyme action

Answer 10

Lock and key

Induced fit

Question 11

Explain lock and key enzyme action

Answer 11

The active sit is complimentary to the substrates binding site

Question 12

Explain induced fit enzyme action

Answer 12

The active site slightly changes to accommodate binding site of substrate
- it is the most accepted model by scientists today (induced fit model)

Question 13

What don’t enzymes do?

Answer 13

They do not change the end product. The inputs and outputs do not change but the reaction simply occurs at a fast rate when enzymes are present

Question 14

Can enzymes join together?

Answer 14

Enzymes can join substrate molecules together or they can may break down a substrate molecule into two smaller ones.

Question 15

What are the types of reactions

Answer 15

Anabolism and catabolism

Question 16

Define anabolism

Answer 16

Taking something small and assembling them together (building reaction)
Eg, Production of proteins from amino acids

Question 17

Define catabolic

Answer 17

Breaking down. Taking something bigger and making it smaller.
Eg. The breakdown of glucose

Question 18

Factors that affect enzyme activity

Answer 18

• temperature
• pH
• substrate concentration
• enzyme concentration
• inhibitors
• different enzymes require different conditions to work effectively.

Question 19

What is the optimum temperature?

Answer 19

Humans enzymes work at an optimum temperature of 37 degrees.

Question 20

Explain factor - Temperture

Answer 20

When temperature is too low, enzymes can not work because they are INACTIVE.
As the temperature increases, the rate if reaction also increase until the optimum temperature.
Beyond this temperature, bonds begin to destabilize changing the overall shape of the enzyme, the enzyme is deemed permanently DENATURED,

Question 21

Example of denatured

Answer 21

Patronized milk

- change shape and cannot be used again

Question 22

What are coenzymes

Answer 22

They are small molecules that Ian enzymes eg. Some vitamins

Question 23

Zymogens or proenzymes

Answer 23

• are inactive precursors of enzymes
• Pepsin is synthesized as pepsinogen, trypsin is synthesized as trypsinogen. These zymogens are activated only when they have been secreted in the gastrointestinal tract.

Question 24

What are the two types of inhibitors?

Answer 24

Competitive and non competitive

Question 25

Define competitive

Answer 25

Competitive- competiting for the active sit

When the inhibitor is bound to enzyme then substrate cannt attach

Question 26

Defiant non competitive inhibitor

Answer 26

Non substrate changes the active site so does not work. And attached to somewhere else on the enzyme.