Question 1

In an enzymatic reaction in a test tube, the reaction will eventually reach equilibrium. Why does this not happen in living organisms?

Accepted Answer

In a cell, the product may be ...

Question 2

Examples of cofactors include:

Accepted Answer

A)   Zn+2, Mg+2, and Ni+2.
B)   biotin and thiamine pyrophosphate.
C)   pyridoxal phosphate and coenzyme A.
D)   B and C.
E)   A, B, and C.F) B) and C)
G) None of the above

Question 3

How is free energy useful for understanding enzyme function?

Accepted Answer

Free energy (∆G) is the key thermodynami...

Question 4

For the two reactions (a)  A → B ∆G°′ = 2 kJ mol−1, and (b)  X → Y ∆G°′ = −3.5 kJ mol−1 , which of the following statements is correct?

Accepted Answer

A)   Reaction (a)  is not spontaneous at cellular concentrations.
B)   Reaction (b)  will react very quickly.
C)   Reaction (a)  is a more thermodynamically favorable reaction than is (b) .
D)   Neither reaction is reversible.
E)   None of the above.F) B) and E)
G) A) and B)

Question 5

An enzyme which has been stripped of the small molecules needed for activity is called an __________________.

Accepted Answer

The answer of An enzyme which has been stripped of...

Question 6

An enzyme which loosely binds substrate will have a __________________ level of specificity.

Accepted Answer

low

Question 7

While some enzymes have very specific substrates, others are more promiscuous. What would you suspect is the reason for this?

Accepted Answer

Specificity of binding is separate from catalysis. The specificity of the enzyme for its substrate is due to many weak interactions between the substrate and the amino acids of the protein. Thus for the less specific binding protein, there must be fewer required interactions for binding.

Question 8

The rate of a reaction, or how quickly a reaction will proceed, is best determined by:

Accepted Answer

A)   ∆R
B)   ∆G‡
C)   ∆G°′
D)   ∆H
E)   None of the above.F) B) and C)
G) D) and E)

Question 9

The active site of an enzyme:

Accepted Answer

A)   is a series of amino acids which bind the enzyme.
B)   is a linear sequence of amino acids that react with each other.
C)   binds covalently to the substrate.
D)   allows water to enter into the active site and thereby solvate the substrate.
E)   None of the above.F) A) and E)
G) A) and C)

Question 10

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
-Enzymes will decrease the energy of activation but do not change the ____________ of a chemical reaction.

Accepted Answer

A)  apoenzymes
B)  hydrolyases
C)  active site
D)  transition state
E)  spontaneousF) induced fitG) energyH) prosthetic groupI) lock and keyJ) substrate(s) K) oxidoreductasesL) equilibriaM) F) and I)
N) E) and H)

Question 11

The ∆G°′ for the hydrolysis of ATP to ADP + Pi is approximately −31 kJ/mole. Calculate the equilibrium constant for this reaction (R = 8.314 J/°mol) at the cellular temperature of 37°C. If the cellular concentrations of ATP, ADP, and Pi are 8, 1, and 8 mM, respectively, is the above reaction at equilibrium in the cell?

Accepted Answer

Keq¬ ¬= 1.7 × 105; n...

Question 12

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
-____________: The site on the enzyme where the reaction occurs.

Accepted Answer

A)  apoenzymes
B)  hydrolyases
C)  active site
D)  transition state
E)  spontaneousF) induced fitG) energyH) prosthetic groupI) lock and keyJ) substrate(s) K) oxidoreductasesL) equilibriaM) D) and I)
N) H) and I)

Question 13

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
-A tightly bound cofactor might be called a(n)  ____________.

Accepted Answer

A)  apoenzymes
B)  hydrolyases
C)  active site
D)  transition state
E)  spontaneousF) induced fitG) energyH) prosthetic groupI) lock and keyJ) substrate(s) K) oxidoreductasesL) equilibriaM) A) and E)
N) D) and K)

Question 14

Organic cofactors are referred to as __________________.

Accepted Answer

The answer of Organic cofactors are referred to as __________________....

Question 15

The molecular structure that is short-lived and neither substrate nor product is known as the:

Accepted Answer

A)   substrate analog.
B)   transition state.
C)   free-energy stabilization state.
D)   catalysis state.
E)   equilibrium intermediate.F) A) and C)
G) A) and D)

Question 16

Multiple dilutions and dialysis of a purified protein results in a loss of enzymatic activity. What might be the cause of this? Assume the structure of the protein is retained.

Accepted Answer

The dilution and dialysis must have caus...

Question 17

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
-A reaction that is exergonic will be ____________.

Accepted Answer

A)  apoenzymes
B)  hydrolyases
C)  active site
D)  transition state
E)  spontaneousF) induced fitG) energyH) prosthetic groupI) lock and keyJ) substrate(s) K) oxidoreductasesL) equilibriaM) B) and E)
N) F) and H) E

Question 18

The difference between the standard-state free energy, ΔG°, and the biochemical standard-state free energy is that ΔG°′ refers to the standard free-energy change at __________________.

Accepted Answer

The answer of The difference between the standard-state free energy,...

Question 19

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
-Enzymes that do not have the required cofactor bound are called ____________.

Accepted Answer

A)  apoenzymes
B)  hydrolyases
C)  active site
D)  transition state
E)  spontaneousF) induced fitG) energyH) prosthetic groupI) lock and keyJ) substrate(s) K) oxidoreductasesL) equilibriaM) A) and H)
N) D) and I)

Question 20

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
-Enzymes that transfer electrons are called ____________.

Accepted Answer

A)  apoenzymes
B)  hydrolyases
C)  active site
D)  transition state
E)  spontaneousF) induced fitG) energyH) prosthetic groupI) lock and keyJ) substrate(s) K) oxidoreductasesL) equilibriaM) E) and J)
N) F) and I)

Exam 6: Basic Concepts of Enzyme Action

In an enzymatic reaction in a test tube, the reaction will eventually reach equilibrium. Why does this not happen in living organisms?

Correct Answer
verified
In a cell, the product may be ...
View Answer

Examples of cofactors include:

Correct Answer
verified

How is free energy useful for understanding enzyme function?

Correct Answer
verified
Free energy (∆G) is the key thermodynami...
View Answer

For the two reactions (a) A → B ∆G°′ = 2 kJ mol−1, and (b) X → Y ∆G°′ = −3.5 kJ mol−1 , which of the following statements is correct?

Correct Answer
verified

An enzyme which has been stripped of the small molecules needed for activity is called an __________________.

Correct Answer
verified

An enzyme which loosely binds substrate will have a __________________ level of specificity.

Correct Answer
verified
low

While some enzymes have very specific substrates, others are more promiscuous. What would you suspect is the reason for this?

The rate of a reaction, or how quickly a reaction will proceed, is best determined by:

Correct Answer
verified

The active site of an enzyme:

Correct Answer
verified

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Enzymes will decrease the energy of activation but do not change the ____________ of a chemical reaction.

Correct Answer
verified

Correct Answer
verified
Keq¬ ¬= 1.7 × 105; n...
View Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -____________: The site on the enzyme where the reaction occurs.

Correct Answer
verified

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -A tightly bound cofactor might be called a(n) ____________.

Correct Answer
verified

Organic cofactors are referred to as __________________.

Correct Answer
verified

The molecular structure that is short-lived and neither substrate nor product is known as the:

Correct Answer
verified

Multiple dilutions and dialysis of a purified protein results in a loss of enzymatic activity. What might be the cause of this? Assume the structure of the protein is retained.

Correct Answer
verified
The dilution and dialysis must have caus...
View Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -A reaction that is exergonic will be ____________.

Correct Answer
verified
E

The difference between the standard-state free energy, ΔG°, and the biochemical standard-state free energy is that ΔG°′ refers to the standard free-energy change at __________________.

Correct Answer
verified

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Enzymes that do not have the required cofactor bound are called ____________.

Correct Answer
verified

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Enzymes that transfer electrons are called ____________.

Correct Answer
verified

Exam 6: Basic Concepts of Enzyme Action

In an enzymatic reaction in a test tube, the reaction will eventually reach equilibrium. Why does this not happen in living organisms?

Correct AnswerverifiedIn a cell, the product may be ...View AnswerShow Answer

Examples of cofactors include:

Correct AnswerverifiedShow Answer

How is free energy useful for understanding enzyme function?

Correct AnswerverifiedFree energy (∆G) is the key thermodynami...View AnswerShow Answer

For the two reactions (a) A → B ∆G°′ = 2 kJ mol−1, and (b) X → Y ∆G°′ = −3.5 kJ mol−1 , which of the following statements is correct?

Correct AnswerverifiedShow Answer

An enzyme which has been stripped of the small molecules needed for activity is called an __________________.

Correct AnswerverifiedShow Answer

An enzyme which loosely binds substrate will have a __________________ level of specificity.

Correct Answerverifiedlow

While some enzymes have very specific substrates, others are more promiscuous. What would you suspect is the reason for this?

The rate of a reaction, or how quickly a reaction will proceed, is best determined by:

Correct AnswerverifiedShow Answer

The active site of an enzyme:

Correct AnswerverifiedShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Enzymes will decrease the energy of activation but do not change the ____________ of a chemical reaction.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedKeq¬ ¬= 1.7 × 105; n...View AnswerShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -____________: The site on the enzyme where the reaction occurs.

Correct AnswerverifiedShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -A tightly bound cofactor might be called a(n) ____________.

Correct AnswerverifiedShow Answer

Organic cofactors are referred to as __________________.

Correct AnswerverifiedShow Answer

The molecular structure that is short-lived and neither substrate nor product is known as the:

Correct AnswerverifiedShow Answer

Multiple dilutions and dialysis of a purified protein results in a loss of enzymatic activity. What might be the cause of this? Assume the structure of the protein is retained.

Correct AnswerverifiedThe dilution and dialysis must have caus...View AnswerShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -A reaction that is exergonic will be ____________.

Correct AnswerverifiedE

The difference between the standard-state free energy, ΔG°, and the biochemical standard-state free energy is that ΔG°′ refers to the standard free-energy change at __________________.

Correct AnswerverifiedShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Enzymes that do not have the required cofactor bound are called ____________.

Correct AnswerverifiedShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Enzymes that transfer electrons are called ____________.

Correct AnswerverifiedShow Answer

Correct Answer
verified
In a cell, the product may be ...
View Answer

Correct Answer
verified

Correct Answer
verified
Free energy (∆G) is the key thermodynami...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
low

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Keq¬ ¬= 1.7 × 105; n...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The dilution and dialysis must have caus...
View Answer

Correct Answer
verified
E

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified