Part 4: Enzyme Classification & Naming

Question 1

I. The IUPAC system gives each enzyme a four-digit code. II. Most enzyme names end in “-ase.”

Answer 1

both statements are true.

Question 2

I. Sucrase catalyzes the hydrolysis of sucrose. II. Oxidases catalyze reduction reactions.

Answer 2

only the first statement is true.

Question 3

I. Pepsin and trypsin are common names for digestive enzymes. II. Pepsin is found in the stomach.

Answer 3

both statements are true.

Question 4

I. Hydrolases involve the addition of water. II. Proteases are a sub-group of hydrolases.

Answer 4

both statements are true.

Question 5

I. Isomerases catalyze the rearrangement of atoms within a molecule. II. Glucose isomerase converts glucose to fructose.

Answer 5

both statements are true.

Question 6

I. Ligases join two molecules together. II. DNA ligase is used in genetic engineering.

Answer 6

both statements are true.

Question 7

I. Transferases move functional groups between molecules. II. Hexokinase is a transferase.

Answer 7

both statements are true.

Question 8

I. Lyases break bonds without hydrolysis or oxidation. II. Decarboxylases are examples of lyases.

Answer 8

both statements are true.

Question 9

I. The systematic name of an enzyme is always short and simple. II. The EC number provides a standardized classification.

Answer 9

only the second statement is true.

Question 10

I. Enzyme activity is expressed in moles of substrate converted per time. II. Spectrophotometers are used to test enzyme activity.

Answer 10

both statements are true.