Test Bank For Lehninger Principles Of C) are closed systems
Biochemistry 8th Edition By David L. Nelson; D) are at equilibrium with their surroundings. - ANSWER
Michael M. Cox All Chapters 1-28 LATES B
A dynamic steady state results when The standard free-energy changes of two sequential
A) a molecule stops being degraded chemical reactions are additive only if
B) an organism is at equilibrium with its surroundings A) the reactions share a common intermediate.
C) there is no net energy transfer B) each reaction has a negative ΔG′°
D) the rate of intake or synthesis of a molecule equals C) the overall (net) reaction has a postive ΔG′°.
the rate of its disappearance. - ANSWER C D) the exergonic reaction occurs first. - ANSWER A
If a chemical reaction starts with 1M concentrations each Which of the following has a thioester bond?
of reactants A and B and products C and D, under what A) PEP (phosphoenolpyruvate)
conditions of K′eq and ΔG′° will the reaction proceed in B) ATP
the forward direction (ΔG′° = RT ln K′eq)? C) phosphocreatine
A) If K′eq is greater than 1 and ΔG′° is negative D) acetyl-CoA - ANSWER D
B) If K′eq is 0 and ΔG′° is negative
C) If K′eq is negative and ΔG′° is negative What provides the energy for the synthesis in an RNA
D) If K′eq is less than 1 and ΔG′° is positive. - ANSWER polymer?
A A) The transfer of an energy-rich ribonucleoside
monophosphate to the polymer.
Living cells and organisms B) The hydrolysis of two anhydride bonds in
A) exchange energy but not matter with their ribonucleoside triphosphates.
surroundings. C) The transfer of the γ phosphate of a ribonucleoside
B) exchange energy and material with their surroundings. triphosphate to the polymer.
,D) The transfer of an energy-rich ribonucleoside A) a proton
triphosphate to the polymer. - ANSWER B B) an electron
C) a hydride ion
When a nucleophile attacks the α phosphorous atom of D) a hydrogen atom. - ANSWER C
ATP, what kind of transfer occurs?
A) pyrophosphoryl transfer Which of the following carbon-containing molecules is
B) phosphoryl transfer most fully oxidized?
C) adenylyl transfer A) carbon monoxide
D) adenosine transfer - ANSWER C B) carbon dioxide
C) methane
When dNTPs become depleted in the cell, which of the D) ethanol - ANSWER B
following enzymes will regenerate dNTPs from dNDPs?
A) nucleoside diphosphate kinase The oxidation-reduction reaction Fe2+ + Cu2+ ↔ Fe3+ +
B) polyphosphate kinase Cu+, can be described in terms of two half-reactions: (1)
C) creatine kinase Fe2+ ↔ Fe3+ + e-(2) Cu2+ + e- ↔ Cu+ Which of the
D) adenylate kinase - ANSWER A following statements is true?
A) In the overall reaction at the top, the cupric ion (Cu2+)
Which of the following enzymes can catalyze the is the reducing agent.
conversion of AMP to ADP? B) In half-reaction (2), cupric ion (Cu2+) is being oxidized.
A) nucleoside diphosphate kinase C) In half-reaction (1), Fe3+ and e- constitute a conjugate
B) polyphosphate kinase redox pair.
C) creatine kinase D) In the overall reaction at the top, the ferrous ion
D) adenylate kinase - ANSWER D (Fe2+) is oxidized by the cupric ion (Cu2+). - ANSWER
D
Conversion of NAD+ to NADH is accomplished by the
addition of
,Electrons can be transferred from one molecule (electron D) Under standard conditions, NAD+ is more likely to be
donor) to another molecule (electron acceptor) by all of converted to NADH, than pyruvate is to converted to
the following ways except lactate. - ANSWER B
A) as a hydride ion
B) directly as an electron Which of the following is not a nucleophile that
C) as a proton commonly participates in biochemical reactions?
D) as a hydrogen atom. - ANSWER C A) carbanion
B) hydroxide ion
Which of the following is true of flavin nucleotides? C) phosphorous of a phosphate group
A) They have no reduction potential unless bound to a D) imidazole - ANSWER C
protein.
B) They always accept two electrons Which process does not generate CO2?
C) They are utilized by oxygenases A) the citric acid cycle
D) They act as prosthetic groups - ANSWER D B) the conversion of pyruvate to lactic acid
C) the conversion of pyruvate to acetyl-CoA
Below are the standard reduction potentials (E′°) for two D) the conversion of pyruvate to ethanol - ANSWER B
conjugate redox pair: Pyruvate-/lactate- E′° = -0.185
NAD+/NADH E′° = -0.320 Which of the following is true about the fermentation of
Which of the following is true? glucose?
A) The pyruvate/lactate conjugate redox pair has a A) It can occur under aerobic or anaerobic conditions,
greater tendency to lose electrons than the NAD+/NADH depending on the products generated.
redox pair. B) There is no net yield of ATP.
B) Pyruvate has a greater affinity for electrons than NAD+ C) The hydrogen to carbon ratio (H:C) of the reactants
C) NAD+ is a reducing agent and products remains the same.
D) It always generates CO2. - ANSWER C
, Glycogen is degraded in a B) when ATP is depleted
A) phosphorylation reaction C) when O2 is depleted
B) hydrolysis reaction D) when NADH is depleted - ANSWER C
C) dephosphorylation reaction
D) phosphorolysis reaction. - ANSWER D The enzyme that converts 3-phosphoglycerate to 2-
phosphoglycerate is a
Which of the following sugars does not get converted to A) transferase
D-glucose before entering the glycolytic pathway? B) kinase.
A) D-fructose C) mutase.
B) glycogen D) phosphorylase. - ANSWER C
C) sucrose
D) lactose - ANSWER A Glycolysis and the pentose phosphate pathway are the
same in that
Which of the following steps occurs during the payoff A) they both generate NADPH
phase of glycolysis? B) they both generate ATP
A) the conversion of phosphoenolpyruvate to pyruvate C) they both involve the oxidation of glucose
B) the conversion of fructose 6-phosphate to fructose D) they are reversible. - ANSWER C
1,6-biphosphate
C) the conversion of glucose 6-phosphate to fructose 6- Which of the following reactions is catalyzed by
phosphate transaldolase?
D) the conversion of glucose to glucose 6-phosphate - A) xylulose 5-phosphate + ribose 5-phosphate ⇔
ANSWER A glyceraldehyde 3-phosphate + sedoheptulose 7-
phosphate
Under what conditions will lactic acid accumulate in B) ribose 5-phosphate ⇔xylulose 5-phosphate
skeletal muscle?
A) when citric acid enzymes are depleted
Biochemistry 8th Edition By David L. Nelson; D) are at equilibrium with their surroundings. - ANSWER
Michael M. Cox All Chapters 1-28 LATES B
A dynamic steady state results when The standard free-energy changes of two sequential
A) a molecule stops being degraded chemical reactions are additive only if
B) an organism is at equilibrium with its surroundings A) the reactions share a common intermediate.
C) there is no net energy transfer B) each reaction has a negative ΔG′°
D) the rate of intake or synthesis of a molecule equals C) the overall (net) reaction has a postive ΔG′°.
the rate of its disappearance. - ANSWER C D) the exergonic reaction occurs first. - ANSWER A
If a chemical reaction starts with 1M concentrations each Which of the following has a thioester bond?
of reactants A and B and products C and D, under what A) PEP (phosphoenolpyruvate)
conditions of K′eq and ΔG′° will the reaction proceed in B) ATP
the forward direction (ΔG′° = RT ln K′eq)? C) phosphocreatine
A) If K′eq is greater than 1 and ΔG′° is negative D) acetyl-CoA - ANSWER D
B) If K′eq is 0 and ΔG′° is negative
C) If K′eq is negative and ΔG′° is negative What provides the energy for the synthesis in an RNA
D) If K′eq is less than 1 and ΔG′° is positive. - ANSWER polymer?
A A) The transfer of an energy-rich ribonucleoside
monophosphate to the polymer.
Living cells and organisms B) The hydrolysis of two anhydride bonds in
A) exchange energy but not matter with their ribonucleoside triphosphates.
surroundings. C) The transfer of the γ phosphate of a ribonucleoside
B) exchange energy and material with their surroundings. triphosphate to the polymer.
,D) The transfer of an energy-rich ribonucleoside A) a proton
triphosphate to the polymer. - ANSWER B B) an electron
C) a hydride ion
When a nucleophile attacks the α phosphorous atom of D) a hydrogen atom. - ANSWER C
ATP, what kind of transfer occurs?
A) pyrophosphoryl transfer Which of the following carbon-containing molecules is
B) phosphoryl transfer most fully oxidized?
C) adenylyl transfer A) carbon monoxide
D) adenosine transfer - ANSWER C B) carbon dioxide
C) methane
When dNTPs become depleted in the cell, which of the D) ethanol - ANSWER B
following enzymes will regenerate dNTPs from dNDPs?
A) nucleoside diphosphate kinase The oxidation-reduction reaction Fe2+ + Cu2+ ↔ Fe3+ +
B) polyphosphate kinase Cu+, can be described in terms of two half-reactions: (1)
C) creatine kinase Fe2+ ↔ Fe3+ + e-(2) Cu2+ + e- ↔ Cu+ Which of the
D) adenylate kinase - ANSWER A following statements is true?
A) In the overall reaction at the top, the cupric ion (Cu2+)
Which of the following enzymes can catalyze the is the reducing agent.
conversion of AMP to ADP? B) In half-reaction (2), cupric ion (Cu2+) is being oxidized.
A) nucleoside diphosphate kinase C) In half-reaction (1), Fe3+ and e- constitute a conjugate
B) polyphosphate kinase redox pair.
C) creatine kinase D) In the overall reaction at the top, the ferrous ion
D) adenylate kinase - ANSWER D (Fe2+) is oxidized by the cupric ion (Cu2+). - ANSWER
D
Conversion of NAD+ to NADH is accomplished by the
addition of
,Electrons can be transferred from one molecule (electron D) Under standard conditions, NAD+ is more likely to be
donor) to another molecule (electron acceptor) by all of converted to NADH, than pyruvate is to converted to
the following ways except lactate. - ANSWER B
A) as a hydride ion
B) directly as an electron Which of the following is not a nucleophile that
C) as a proton commonly participates in biochemical reactions?
D) as a hydrogen atom. - ANSWER C A) carbanion
B) hydroxide ion
Which of the following is true of flavin nucleotides? C) phosphorous of a phosphate group
A) They have no reduction potential unless bound to a D) imidazole - ANSWER C
protein.
B) They always accept two electrons Which process does not generate CO2?
C) They are utilized by oxygenases A) the citric acid cycle
D) They act as prosthetic groups - ANSWER D B) the conversion of pyruvate to lactic acid
C) the conversion of pyruvate to acetyl-CoA
Below are the standard reduction potentials (E′°) for two D) the conversion of pyruvate to ethanol - ANSWER B
conjugate redox pair: Pyruvate-/lactate- E′° = -0.185
NAD+/NADH E′° = -0.320 Which of the following is true about the fermentation of
Which of the following is true? glucose?
A) The pyruvate/lactate conjugate redox pair has a A) It can occur under aerobic or anaerobic conditions,
greater tendency to lose electrons than the NAD+/NADH depending on the products generated.
redox pair. B) There is no net yield of ATP.
B) Pyruvate has a greater affinity for electrons than NAD+ C) The hydrogen to carbon ratio (H:C) of the reactants
C) NAD+ is a reducing agent and products remains the same.
D) It always generates CO2. - ANSWER C
, Glycogen is degraded in a B) when ATP is depleted
A) phosphorylation reaction C) when O2 is depleted
B) hydrolysis reaction D) when NADH is depleted - ANSWER C
C) dephosphorylation reaction
D) phosphorolysis reaction. - ANSWER D The enzyme that converts 3-phosphoglycerate to 2-
phosphoglycerate is a
Which of the following sugars does not get converted to A) transferase
D-glucose before entering the glycolytic pathway? B) kinase.
A) D-fructose C) mutase.
B) glycogen D) phosphorylase. - ANSWER C
C) sucrose
D) lactose - ANSWER A Glycolysis and the pentose phosphate pathway are the
same in that
Which of the following steps occurs during the payoff A) they both generate NADPH
phase of glycolysis? B) they both generate ATP
A) the conversion of phosphoenolpyruvate to pyruvate C) they both involve the oxidation of glucose
B) the conversion of fructose 6-phosphate to fructose D) they are reversible. - ANSWER C
1,6-biphosphate
C) the conversion of glucose 6-phosphate to fructose 6- Which of the following reactions is catalyzed by
phosphate transaldolase?
D) the conversion of glucose to glucose 6-phosphate - A) xylulose 5-phosphate + ribose 5-phosphate ⇔
ANSWER A glyceraldehyde 3-phosphate + sedoheptulose 7-
phosphate
Under what conditions will lactic acid accumulate in B) ribose 5-phosphate ⇔xylulose 5-phosphate
skeletal muscle?
A) when citric acid enzymes are depleted
