Question 1

Which statement best describes how enzymes affect the activation energy of a chemical reaction in the body?

Accepted Answer

Enzymes lower the activation energy, allowing reactions to occur faster.

Question 2

Which of the following is the correct general equation for an enzyme-catalyzed reaction?

Accepted Answer

$E + S \rightarrow ES \rightarrow E + P$

Question 3

A patient is unable to digest lactose due to a deficiency in the enzyme lactase. Which class of enzyme does lactase belong to?

Accepted Answer

Hydrolases

Question 4

Which of the following best describes the lock-and-key model of enzyme action?

Accepted Answer

The enzyme's active site is rigid and only binds substrates that exactly fit.

Question 5

Which enzyme class is responsible for transferring a functional group from one molecule to another?

Accepted Answer

Transferases

Question 6

What is the main difference between the lock-and-key and induced-fit models of enzyme action?

Accepted Answer

The induced-fit model describes a flexible active site that adapts to the substrate, while the lock-and-key model describes a rigid active site.

Question 7

Which of the following statements about isoenzymes is TRUE?

Accepted Answer

Isoenzymes are different forms of an enzyme that catalyze the same reaction in different cells or tissues.

Question 8

Which enzyme class uses ATP energy to form bonds between molecules?

Accepted Answer

Ligases

Question 9

During the hydrolysis of lactose, which products are released after the enzyme-substrate complex breaks down?

Accepted Answer

Galactose and glucose

Question 10

Which of the following best describes the role of amino acid R groups in the active site of an enzyme?

Accepted Answer

They bind the substrate and help catalyze the reaction.

Question 11

A scientist discovers a new enzyme that rearranges atoms within a molecule to form an isomer. Which class does this enzyme belong to?

Accepted Answer

Isomerases

Question 12

Which statement about enzyme names is correct?

Accepted Answer

Enzyme names are derived by replacing the end of the reacting compound with '-ase'.

Question 13

Which of the following is NOT a function of the active site of an enzyme?

Accepted Answer

Changing the enzyme's primary structure

Question 14

Which enzyme class catalyzes hydrolysis reactions?

Accepted Answer

Hydrolases

Question 15

A medical test detects elevated levels of a specific isoenzyme in the blood. What does this most likely indicate?

Accepted Answer

A particular tissue or organ may be damaged or diseased.

Question 16

Which of the following is a correct example of an enzyme name and its function?

Accepted Answer

Oxidase catalyzes an oxidation reaction.

Question 17

Which of the following statements about enzyme reuse is correct?

Accepted Answer

Enzymes are regenerated after the reaction and can be used repeatedly.

Question 18

Which enzyme class is responsible for oxidation-reduction reactions?

Accepted Answer

Oxidoreductases

Question 19

In the induced-fit model, what happens to the enzyme when the substrate binds?

Accepted Answer

The enzyme's shape adapts to fit the substrate.

Question 20

Which of the following best explains why enzymes are specific to their substrates?

Accepted Answer

The active site of the enzyme has a unique shape that fits only certain substrates.

Enzymes: Biological Catalysts, Classification, and Mechanisms (Chapter 16 Study Notes)

Study Guide - Practice Questions