Test in Ten: Enzymes

The graph shows changing energy levels during a reaction, with and without the presence of the enzyme specific to this reaction.

What is the activation energy of the reaction without the enzyme?

• A

• B

• C

• D

The diagram shows an experiment to investigate the action of amylase on a 1.0 g cube of potato. The potato contains starch.

After 15 minutes at 20 degrees Celsius, 0.25 g of starch has been converted to sugar.

The experiment is repeated at 30 degrees Celsius.

How much starch is converted to sugar?

• 0.15 g

• 0.25 g

• 0.50 g

• 1.0 g

What happens when an enzyme catalyses a reaction?

• The activation energy is raised.

• The enzyme molecule cannot be used again.

• The products are different in the presence of the enzyme.

• The speed of the reaction changes.

The graph shows the results of an experiment on enzyme activity.

Which label for the x-axis is correct?

• concentration of enzyme-substrate complex

• pH

• temperature

• time

The diagram represents the lock and key theory of an enzyme reaction which takes place in the mouth.

Name A, B and C.

Biological washing powders (laundry detergents) contain one or more enzymes.

Suggest the advantages of using biological washing powders compared to those without enzymes.