Question 1

Which molecule is NOT considered a universal electron carrier?

Accepted Answer

A)   NADH
B)   ATPF
C)   ADH2
D)   FMNH2
E)   both ATPF and FMNH2F) A) and C)
G) D) and E)

Question 2

In general, when ATP hydrolysis is coupled to an energy-requiring reaction, the actual reaction often consists of the transfer of a phosphate group from ATP to another substrate, rather than an actual hydrolysis of the ATP. Explain.

Accepted Answer

When ATP hydrolysis is coupled to an ene...

Question 3

Given  $\Delta$ G'° for each of the following reactions,

Accepted Answer

It seems like there is some information ...

Question 4

Which compound is classified as high energy?

Accepted Answer

A)   phosphoarginine
B)   succinyl-CoA
C)   fatty acid-CoA
D)   All of the answers are correct.
E)   None of the answers is correct.F) A) and D)
G) B) and C)

Question 5

The expression $\Delta$G = $\Delta$G'° + RT ln Keq' for the actual free-energy change for the reaction A + B $\rightarrow$ C + D is incorrect. Why is it wrong, and what is the correct expression for the real free-energy change of this reaction?

Accepted Answer

The given expression for the actual free...

Question 6

Which statement about NAD+ and NADH is FALSE?

Accepted Answer

A)   NAD+ is oxidized to NADH by  α\alphaα -ketoglutarate dehydrogenase.
B)   Lactate dehydrogenase binds NAD+ tightly in the Rossmann fold.
C)   NAD+ accepts both electrons as a hydride ion.
D)   NAD+ is oxidized to NADH by  α\alphaα -ketoglutarate dehydrogenase, and lactate dehydrogenase binds NAD+ tightly in the Rossmann fold.
E)   NAD+ is oxidized to NADH by  α\alphaα -ketoglutarate dehydrogenase, and NAD+ accepts both electrons as a hydride ion. F) A) and B)
G) A) and C)

Question 7

Which redox reaction(s)  will NOT proceed as written if the initial concentrations of reactants and products are equal? I. pyruvate + NADH  →\rightarrow→   lactate + NAD+
II. FADH2 + NAD+  →\rightarrow→   FAD + NADH + H+
III. succinate + NAD+  →\rightarrow→  fumarate + NADH + H+ 
IV. NADH + H+ + ubiquinone  →\rightarrow→  NAD+ + ubiquinol
V. cytochrome c-Fe3+ + cytochrome b-Fe2+  →\rightarrow→  cytochrome c-Fe2+ + cytochrome b-Fe3+

Accepted Answer

A)   I and IV
B)   I, IV, and V
C)   II
D)   II and III
E)   IV and V F) B) and C)
G) A) and E) D

Question 8

Explain why each of the following statements is FALSE.
(a) In a reaction under standard conditions, only the reactants are fixed at 1 M.
(b) When $\Delta$G'° is positive, Keq' > 1.
(c) $\Delta$G and $\Delta$G'° mean the same thing.
(d) When $\Delta$G'° = 1.0 kJ/mol, Keq' = 1.

Accepted Answer

(a) In a reaction under standard conditi...

Question 9

Which statement regarding redox reactions is TRUE?

Accepted Answer

A)   NADH and FADH2 are major electron acceptors in the oxidation of fuel molecules.
B)   In glycolysis, the conversion of 2-phosphpoglycerate to phosphoenolpyruvate is a redox reaction.
C)   In a redox reaction, the oxidation state of the substrate remains unchanged.
D)   A redox reaction is spontaneous when the substrate has a greater reduction potential than the product.
E)   The Nerst equation relates the standard reduction potential of a redox pair to its actual reduction potential at any concentration of either the oxidized or reduced form of the species.F) A) and E)
G) B) and D)

Question 10

If the equilibrium constant for the dissociation of lactic acid is 1.38 × 10-4, what is the  Δ\DeltaΔ G°' for this reaction?

Accepted Answer

A)   16.3kJ/mol
B)   -16.3 kJ/mol
C)   16.96 kJ/mol
D)   -16.96 kJ/mol
E)   27.5 kJ/mol F) C) and D)
G) A) and B) A

Question 11

Which statement is TRUE regarding coupled reactions?

Accepted Answer

A)   The standard free energy changes of the coupled reactions are additive, and their equilibrium constants are multiplicative.
B)   The coupled reactions must share a common intermediate.
C)   The free energy of the endergonic reaction must be greater in magnitude than the free energy of the exergonic reaction.
D)   The standard free energy changes of the coupled reactions are additive, their equilibrium constants are multiplicative, and the coupled reactions must share a common intermediate.
E)   None of the statements is true.F) B) and E)
G) D) and E)

Question 12

Which is the MOST oxidized carbon atom in a ketohexose sugar?

Accepted Answer

A)   C1
B)   C2
C)   C3
D)   C5
E)   C6F) A) and B)
G) D) and E)

Question 13

Glycerol 3-phosphate dehydrogenase catalyzes the following reversible reaction:
glycerol 3-phosphate + NAD+ $\rightarrow$ NADH + H+ + dihydroxyacetone phosphate
Given the standard reduction potentials below, calculate $\Delta$G'° for the glycerol 3-phosphate dehydrogenase reaction, proceeding from left to right as shown. Show your work. (The Faraday constant, , is 96.48 kJ/V · mol.)
dihydroxyacetone phosphate + 2e- + 2H+ $\rightarrow$ glycerol 3-phosphate
E'° = -0.29 V
NAD+ + H+ + 2e- $\rightarrow$ NADH
E'° = -0.32 V

Accepted Answer

To calculate the standard Gibbs free ene...

Question 14

During glycolysis, glucose 1-phosphate is converted to fructose 6-phosphate in two successive reactions: glucose 1-phosphate  →\rightarrow→   glucose 6-phosphate
 Δ\DeltaΔ G'° = -7.1 kJ/mol
Glucose 6-phosphate  →\rightarrow→   fructose 6-phosphate
 Δ\DeltaΔ G'° = +1.7 kJ/mol
 Δ\DeltaΔ G'° for the overall reaction is:

Accepted Answer

A)   -8.8 kJ/mol.
B)   -7.1 kJ/mol.
C)   -5.4 kJ/mol.
D)   +5.4 kJ/mol.
E)   +8.8 kJ/mol. F) A) and E)
G) B) and C)

Question 15

Which carbon atom is in the MOST reduced state?

Accepted Answer

A)   a carbon in an alkyl group
B)   a carbon in an aldehyde group
C)   a carbon in a ketone group
D)   a carbon in a carboxylic acid group
E)   a carbon in an alcohol groupF) A) and B)
G) None of the above

Question 16

Which compound has the LARGEST negative value for the standard free-energy change ( Δ\DeltaΔ G'°)  upon hydrolysis?

Accepted Answer

A)   acetic anhydride
B)   glucose 6-phosphate
C)   glutamine
D)   glycerol 3-phosphate
E)   lactose F) C) and E)
G) A) and D)

Question 17

Which statement is NOT true regarding the biochemical standard state?

Accepted Answer

A)   The [H+] is 10-7M.
B)   Temperature is 28°C.
C)   All reactants and products are present at 1 M concentrations.
D)   The pressure is 1 atm.
E)   The concentration of water is essentially constant at 55.5 M.F) C) and D)
G) A) and B)

Question 18

What is the CORRECT order of substances in terms of electronegativity, greatest to least?

Accepted Answer

A)   H  →\rightarrow→   C  →\rightarrow→   N  →\rightarrow→  S  →\rightarrow→   O
B)   H  →\rightarrow→   C  →\rightarrow→  S  →\rightarrow→   O  →\rightarrow→  N
C)   O  →\rightarrow→   S →\rightarrow→   N  →\rightarrow→  C  →\rightarrow→   H
D)   N  →\rightarrow→   O  →\rightarrow→  S →\rightarrow→  H →\rightarrow→  C
E)   O  →\rightarrow→   N  →\rightarrow→   S  →\rightarrow→  C  →\rightarrow→   O F) B) and C)
G) None of the above

Question 19

When a mixture of glucose 6-phosphate and fructose 6-phosphate is incubated with the enzyme phosphohexose isomerase (which catalyzes the interconversion of these two compounds)  until equilibrium is reached, the final mixture contains twice as much glucose 6-phosphate as fructose 6-phosphate. Which one of the following statements is best applied to this reaction outlined below? (R = 8.315 J/mol · K; T = 298 K)  glucose 6-phosphate  →\rightarrow→ fructose 6-phosphate

Accepted Answer

A)    Δ\DeltaΔ G'° is incalculably large and negative.
B)    Δ\DeltaΔ G'° is -1.72 kJ/mol.
C)    Δ\DeltaΔ G'° is zero.
D)    Δ\DeltaΔ G'° is +1.72 kJ/mol.
E)    Δ\DeltaΔ G'° is incalculably large and positive. F) A) and B)
G) C) and D) D

Question 20

Under standard conditions, ATP can be used in phosphate-transfer reactions to generate which molecule?

Accepted Answer

A)   phosphocreatine
B)   glycerol-3-phosphate
C)   phosphoenolpyruvate
D)   1,3-bisphosphoglycerate
E)   All of the answers are correct.F) A) and B)
G) A) and E)

Exam 13: Bioenergetics and Biochemical Reaction Types

Which molecule is NOT considered a universal electron carrier?

Correct Answer
verified

In general, when ATP hydrolysis is coupled to an energy-requiring reaction, the actual reaction often consists of the transfer of a phosphate group from ATP to another substrate, rather than an actual hydrolysis of the ATP. Explain.

Correct Answer
Answered by ExamLex AI
When ATP hydrolysis is coupled to an ene...
View Answer

Given $\Delta$ G'° for each of the following reactions, $Given \Delta G'° for each of the following reactions,$

Correct Answer
Answered by ExamLex AI
It seems like there is some information ...
View Answer

Which compound is classified as high energy?

Correct Answer
verified

The expression $\Delta$ G = $\Delta$ G'° + RT ln K_eq' for the actual free-energy change for the reaction A + B $\rightarrow$ C + D is incorrect. Why is it wrong, and what is the correct expression for the real free-energy change of this reaction?

Correct Answer
Answered by ExamLex AI
The given expression for the actual free...
View Answer

Which statement about NAD⁺ and NADH is FALSE?

Correct Answer
verified

Correct Answer
verified
D

Explain why each of the following statements is FALSE. (a) In a reaction under standard conditions, only the reactants are fixed at 1 M. (b) When $\Delta$ G'° is positive, K_eq' > 1. (c) $\Delta$ G and $\Delta$ G'° mean the same thing. (d) When $\Delta$ G'° = 1.0 kJ/mol, K_eq' = 1.

Correct Answer
Answered by ExamLex AI
(a) In a reaction under standard conditi...
View Answer

Which statement regarding redox reactions is TRUE?

Correct Answer
verified

If the equilibrium constant for the dissociation of lactic acid is 1.38 × 10^-⁴, what is the $\Delta$ G°' for this reaction?

Correct Answer
verified
A

Which statement is TRUE regarding coupled reactions?

Correct Answer
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Which is the MOST oxidized carbon atom in a ketohexose sugar?

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
To calculate the standard Gibbs free ene...
View Answer

Correct Answer
verified

Which carbon atom is in the MOST reduced state?

Correct Answer
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Which compound has the LARGEST negative value for the standard free-energy change ( $\Delta$ G'°) upon hydrolysis?

Correct Answer
verified

Which statement is NOT true regarding the biochemical standard state?

Correct Answer
verified

What is the CORRECT order of substances in terms of electronegativity, greatest to least?

Correct Answer
verified

Correct Answer
verified
D

Under standard conditions, ATP can be used in phosphate-transfer reactions to generate which molecule?

Correct Answer
verified

Exam 13: Bioenergetics and Biochemical Reaction Types

Which molecule is NOT considered a universal electron carrier?

Correct AnswerverifiedShow Answer

In general, when ATP hydrolysis is coupled to an energy-requiring reaction, the actual reaction often consists of the transfer of a phosphate group from ATP to another substrate, rather than an actual hydrolysis of the ATP. Explain.

Correct AnswerAnswered by ExamLex AIWhen ATP hydrolysis is coupled to an ene...View AnswerShow Answer

Given Δ\DeltaΔ G'° for each of the following reactions,

Correct AnswerAnswered by ExamLex AIIt seems like there is some information ...View AnswerShow Answer

Which compound is classified as high energy?

Correct AnswerverifiedShow Answer

The expression Δ\DeltaΔ G = Δ\DeltaΔ G'° + RT ln Keq' for the actual free-energy change for the reaction A + B →\rightarrow→ C + D is incorrect. Why is it wrong, and what is the correct expression for the real free-energy change of this reaction?

Correct AnswerAnswered by ExamLex AIThe given expression for the actual free...View AnswerShow Answer

Which statement about NAD+ and NADH is FALSE?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedD

Explain why each of the following statements is FALSE. (a) In a reaction under standard conditions, only the reactants are fixed at 1 M. (b) When Δ\DeltaΔ G'° is positive, Keq' > 1. (c) Δ\DeltaΔ G and Δ\DeltaΔ G'° mean the same thing. (d) When Δ\DeltaΔ G'° = 1.0 kJ/mol, Keq' = 1.

Correct AnswerAnswered by ExamLex AI(a) In a reaction under standard conditi...View AnswerShow Answer

Which statement regarding redox reactions is TRUE?

Correct AnswerverifiedShow Answer

If the equilibrium constant for the dissociation of lactic acid is 1.38 × 10-4, what is the Δ\DeltaΔ G°' for this reaction?

Correct AnswerverifiedA

Which statement is TRUE regarding coupled reactions?

Correct AnswerverifiedShow Answer

Which is the MOST oxidized carbon atom in a ketohexose sugar?

Correct AnswerverifiedShow Answer

Correct AnswerAnswered by ExamLex AITo calculate the standard Gibbs free ene...View AnswerShow Answer

Correct AnswerverifiedShow Answer

Which carbon atom is in the MOST reduced state?

Correct AnswerverifiedShow Answer

Which compound has the LARGEST negative value for the standard free-energy change ( Δ\DeltaΔ G'°) upon hydrolysis?

Correct AnswerverifiedShow Answer

Which statement is NOT true regarding the biochemical standard state?

Correct AnswerverifiedShow Answer

What is the CORRECT order of substances in terms of electronegativity, greatest to least?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedD

Under standard conditions, ATP can be used in phosphate-transfer reactions to generate which molecule?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
When ATP hydrolysis is coupled to an ene...
View Answer

Given $\Delta$ G'° for each of the following reactions, $Given \Delta G'° for each of the following reactions,$

Correct Answer
Answered by ExamLex AI
It seems like there is some information ...
View Answer

Correct Answer
verified

The expression $\Delta$ G = $\Delta$ G'° + RT ln K_eq' for the actual free-energy change for the reaction A + B $\rightarrow$ C + D is incorrect. Why is it wrong, and what is the correct expression for the real free-energy change of this reaction?

Correct Answer
Answered by ExamLex AI
The given expression for the actual free...
View Answer

Which statement about NAD⁺ and NADH is FALSE?

Correct Answer
verified

Correct Answer
verified
D

Explain why each of the following statements is FALSE. (a) In a reaction under standard conditions, only the reactants are fixed at 1 M. (b) When $\Delta$ G'° is positive, K_eq' > 1. (c) $\Delta$ G and $\Delta$ G'° mean the same thing. (d) When $\Delta$ G'° = 1.0 kJ/mol, K_eq' = 1.

Correct Answer
Answered by ExamLex AI
(a) In a reaction under standard conditi...
View Answer

Correct Answer
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If the equilibrium constant for the dissociation of lactic acid is 1.38 × 10^-⁴, what is the $\Delta$ G°' for this reaction?

Correct Answer
verified
A

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
To calculate the standard Gibbs free ene...
View Answer

Correct Answer
verified

Correct Answer
verified

Which compound has the LARGEST negative value for the standard free-energy change ( $\Delta$ G'°) upon hydrolysis?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
D

Correct Answer
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