Enzymes: 22 Questions

True or False: Enzymes are designed for very specific chemical reactions:

Which of the following is correct?

a. Apoenzyme + Cofactor = Holoenzyme
b. Apoenzyme – Cofactor = Holoenzyme
c. Apoenzyme = Cofactor – Holoenzyme
d. None

How many enzyme classes are there?

a. Two
b. Four
c. Five
d. Six

Majority of the enzymes are inactive at:

a. At 20 degrees C
b. At 10 degrees C
c. Between 30-40 degrees C
d. Above 70 degrees C

The enzyme that differs in amino acid sequence but catalyzes the same reaction are ___________.

a. Co-factors
b. C0-enzymes
c. Apoenzymes
d. Isoenzymes

The temperature at which the maximum activity of the enzyme occurs is ___________.

a. Optimum temperature
b. Maximum temperature
c. Minimum temperature
d. None

The class of enzymes that catalyzes synthetic reactions where two molecules are joined together and ATP is used is _____________.

a. Hydrolases
b. Lyases
c. Ligases
d. Isomerases

The non-protein organic part of the enzyme is _____________.

a. Co-factor
b. Co-enzyme
c. Apoenzyme
d. Isoenzyme

Pepsin and urease are examples for which class of enzymes?

a. Hydrolases
b. Ligases
c. Oxidoreductases
d. Lyases

Enzymes are special types of:

a. Catalysts
b. Proteins
c. Bacteria
d. Both a and b 
e. All of the above

Enzymes change the _________ of a chemical reaction.

a. Type
b. Rate
c. Reactants
d. Product
e. Yield

Where does the reaction between the enzyme and the substrate take place at?

a. Substrate
b. Activator
c. Active Sight
d. Inhibitor
e. Product

The new molecules or substances released by the enzyme are called:

a. Substrate
b. Activator
c. Active Sight
d. Inhibitor
e. Product

What is the name of the molecule or substance that the enzyme reacts with?

a. Substrate
b. Activator
c. Active Sight
d. Inhibitor
e. Product

True or False: The lower the temperature, the faster the reaction at the enzyme will
occur.

a. True
b. False

A higher ____________ can increase the reaction rate.

a. Concentration of enzyme or substrate
b. pH
c. Number of inhibitors
d. All of the above
e. None of the above

Which of the following pH levels will most likely NOT affect enzyme activity?

a. 2 (very low pH)
b. 3
c. 7
d. 12
e. 14 (very high pH)

What are inhibitors?

a. Molecules that make enzymes
b. Molecules that slow down or stop enzymes
c. Molecules that speed up enzymes
d. Molecules that replace enzymes
e. Molecules that combine and separate enzymes

Inactive enzymes which are not bound to their cofactors are called:

a. Apoenzymes
b. Coenzymes
c. Enzyme Inhibitors
d. Holoenzymes

The ‘lock and key hypothesis’ mechanism is related with:

a. Digestion of fat in the body
b. For enzyme specificity
c. For the formation of vacuole
d. Explosives

Which of the following statement is/are correct about Enzyme:

a. An Enzyme is a protein and is used as a catalyst to accelerate the reaction
b. Life would not exist without the presence of enzymes
c. Enzymes participate in cellular metabolic processes
d. All of the above
e. None of the above

Name an enzyme that digest fat?

a. Lipase
b. Sucrase
c. Maltase
d. Fructose
e. Fatty acid