Lehninger Biochemistry Chapter 6 Multiple Choice Questions And Answers Graded A+.
One of the enzymes involved in glycolysis, aldolase, requires Zn2+ for catalysis. Under conditions of zinc deficiency, when the enzyme may lack zinc, it would be referred to as the:
A) apoenzyme.
B)...
One of the enzymes involved in glycolysis, aldolase, requires Zn2+ for catalysis. Under
conditions of zinc deficiency, when the enzyme may lack zinc, it would be referred to as
the:
A) apoenzyme.
B) coenzyme.
C) holoenzyme.
D) prosthetic group.
E) substrate. - correct answer. A) apoenzyme.
Which one of the following is not among the six internationally accepted classes of
enzymes?
A) Hydrolases
B) Ligases
C) Oxidoreductases
D) Polymerases
E) Transferases - correct answer. D) Polymerases
Enzymes are potent catalysts because they:
A) are consumed in the reactions they catalyze.
B) are very specific and can prevent the conversion of products back to substrates.
C) drive reactions to completion while other catalysts drive reactions to equilibrium.
D) increase the equilibrium constants for the reactions they catalyze.
E) lower the activation energy for the reactions they catalyze. - correct answer. E)
lower the activation energy for the reactions they catalyze.
, The role of an enzyme in an enzyme-catalyzed reaction is to:
A) bind a transition state intermediate, such that it cannot be converted back to
substrate.
B) ensure that all of the substrate is converted to product.
C) ensure that the product is more stable than the substrate.
D) increase the rate at which substrate is converted into product.
E) make the free-energy change for the reaction more favorable. - correct answer. D)
increase the rate at which substrate is converted into product.
Which one of the following statements is true of enzyme catalysts?
A) Their catalytic activity is independent of pH.
B) They are generally equally active on D and L isomers of a given substrate.
C) They can increase the equilibrium constant for a given reaction by a thousand fold or
more.
D) They can increase the reaction rate for a given reaction by a thousand-fold or more.
E) To be effective, they must be present at the same concentration as their substrate. -
correct answer. D) They can increase the reaction rate for a given reaction by a
thousand-fold or more.
Which one of the following statements is true of enzyme catalysts?
A) They bind to substrates but are never covalently attached to substrate or product.
B) They increase the equilibrium constant for a reaction, thus favoring product
formation.
C) They increase the stability of the product of a desired reaction by allowing
ionizations, resonance, and isomerizations not normally available to substrates.
D) They lower the activation energy for the conversion of substrate to product.
E) To be effective, they must be present at the same concentration as their substrates. -
correct answer. D) They lower the activation energy for the conversion of substrate to
product.
Which of the following statements is false?
A) A reaction may not occur at a detectable rate even though it has a favorable
equilibrium.
B) After a reaction, the enzyme involved becomes available to catalyze the reaction
again.
C) For S P, a catalyst shifts the reaction equilibrium to the right.
D) Lowering the temperature of a reaction will lower the reaction rate.
E) Substrate binds to an enzyme's active site. - correct answer. C) For S P, a catalyst
shifts the reaction equilibrium to the right.
Enzymes differ from other catalysts in that only enzymes:
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller techgrades. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $12.99. You're not tied to anything after your purchase.
