Enzymes.

Question 1

What is an extracellular enzyme?

Answer 1

An enzyme that works outside the cell.

Question 2

What is an intracellular enzyme?

Answer 2

An enzyme that works inside the cell.

Question 3

Name an intracellular enzyme.

Answer 3

• Catalase

Question 4

Name extracellular enzymes.

Answer 4

• Trypsin
• Amylose

Question 5

What determines the shape of the active site?

Answer 5

Tertiary bonds.

Question 6

What is a prosthetic group?

Answer 6

A cofactor that is permanently bound, by covalent bonds, to an enzyme.

Question 7

Give an examples of prosthetic groups.

Answer 7

• A zinc ion in carbonic anhydrase. (Zn2+)
• Haem prosthetic group in haemoglobin.

Question 8

What is a cofactor?

Answer 8

A substance that has to be present to ensure that an enzyme-catalysed reaction takes place at an appropriate rate.

Question 9

What is a coenzyme?

Answer 9

Small organic non-protein molecules that bind temporarily to the active site.

Question 10

What is an example of a coenzyme?

Answer 10

• b12.

Question 11

What are the two models of enzyme action?

Answer 11

• Lock-and-key.
• Induced fit.

Question 12

Outline the mechanism of enzyme action.

Question 13

What are the 4 factors that effect the rate of enzyme catalysed reactions?

Answer 13

• Temperature
• pH
• Substrate concentration
• Enzyme concentration.

Question 14

Why are enzymes referred to as “biological catalysts” ?

Question 15

How do enzymes impact the rate of reaction?

Answer 15

Enzymes lower the activation energy needed to active the reaction.

Question 16

How do you calculate the Q10?

Answer 16

(rate of reaction at (x + 10) °C) ÷ (rate of reaction at x °C)

Question 17

Where does a non-competitive inhibitor bind?

Answer 17

The allosteric site of the enzyme.