What are Enzymes? - Organisation

Question 1

What is a ‘catalyst’?

Answer 1

A substance that speeds up a reaction without being used up

Question 2

What is an ‘enzyme’?

Answer 2

A special type of catalyst that is made by a living organism

Question 3

What is the name of special region of an enzyme that binds to the substrate?

Answer 3

Active site

Question 4

What is the model where the substrate has to ‘fit perfectly’ into the active site?

Answer 4

Lock and key

Question 5

What is the model where as the substrate fits into the active site it ‘changes slightly’ to fit?

Answer 5

Induced fit model

Question 6

What is known as the ‘optimum’ mean temp of an enzyme?

Answer 6

The temperature at which enzyme activity is highest before it starts to denature

Question 7

What is it called when an enzyme ‘looses its shape’?

Answer 7

The enzyme is denatured

Question 8

What’s the ‘optimum pH’ for enzymes in and other than the stomach?

Answer 8

Enzymes in the stomach are pH 2
Enzymes other than the stomach are pH 7

Question 9

What does it mean for an enzyme to be ‘denatured’?

Answer 9

The active site of the enzyme has lost its shape so can’t fit with the substrate

Question 10

Explain how increasing the temperature can cause an enzyme to denature.(3marks)

Answer 10

• High temps start to ‘break the bond’
• so the ‘active site start to change shape’
• therefore the active site won’t complement the substrate