Question 1

A reaction at its lowest energy state for the system and with equal rates in the forward and reverse directions is said to be at ________.

Accepted Answer

equilibrium

Question 2

The change in enthalpy (△H) for the complete oxidation of a fatty acid is different depending on whether it occurs via a biochemical pathway or combustion to CO2 and H2O.

Accepted Answer

A) True 
 B)False  False

Question 3

Calculate the △G∘' for the reaction
fructose-6-phosphate → glucose-6-phosphate
given the equilibrium constant is 1.97 and the physiological relevant temperature is 37∘C.

Accepted Answer

-1.75kJ/mol

Question 4

A reaction with a large negative free energy of hydrolysis can be coupled to the synthesis of ATP from ADP and Pi.

Accepted Answer

A) True 
 B)False

Question 5

A reaction at equilibrium can be driven in one direction or the other by changing the ________ of reactants or products.

Accepted Answer

The answer of A reaction at equilibrium can be driven...

Question 6

In a general redox reaction, the reductant becomes oxidized and the oxidant becomes reduced.

Accepted Answer

A) True 
 B)False

Question 7

The equilibrium constant of a reaction:

Accepted Answer

A)  is not related to the change in free energy of the reaction. 
B)  is the same as the mass action ratio when the reaction is displaced from equilibrium. 
C)  can change if the concentration of reactants and products are changed. 
D)  is related to the change in free energy of the reaction. 
E)  cannot be used to determine whether a reaction will proceed in the direction as written under non-standard conditions. 
A)  is not related to the change in free energy of the reaction. 
B)  is the same as the mass action ratio when the reaction is displaced from equilibrium. 
C)  can change if the concentration of reactants and products are changed. 
D)  is related to the change in free energy of the reaction. 
E)  cannot be used to determine whether a reaction will proceed in the direction as written under non-standard conditions.

Question 8

Calculate the equilibrium constant for the enzymatic hydrolysis of 0.1 M glucose-6-phosphate to glucose and inorganic phosphate given that 0.05% of the original glucose-6-phosphate remained after reaching equilibrium and the activity of water is unity.

Accepted Answer

The answer of Calculate the equilibrium constant for the enzymatic...

Question 9

Life is an irreversible process, such that it never comes to equilibrium.

Accepted Answer

A) True 
 B)False

Question 10

A thermodynamically unfavorable reaction can become favorable when coupled to a highly endergonic reaction.

Accepted Answer

A) True 
 B)False

Question 11

A biochemical reaction will proceed in the direction as written if:

Accepted Answer

A) △G = zero. B) △G > 0. C) △G 0. E) △H < 0. A) △G = zero. B) △G > 0. C) △G 0. E) △H < 0.

Question 12

Which of the following statements is FALSE?

Accepted Answer

A)  Entropy is a measure of disorder. 
B)  The entropy of an isolated system will tend to increase to a maximum value. 
C)  Biological systems are highly ordered so entropy changes are not relevant. 
D)  Biological systems expend energy to overcome entropy. 
E)  The entropy of a biological system can decrease. 
A)  Entropy is a measure of disorder. 
B)  The entropy of an isolated system will tend to increase to a maximum value. 
C)  Biological systems are highly ordered so entropy changes are not relevant. 
D)  Biological systems expend energy to overcome entropy. 
E)  The entropy of a biological system can decrease.

Question 13

The △Go of a reaction:

Accepted Answer

A)  will change if the temperature of the reaction is changed. 
B)  will change if the concentration of reactants and products are changed. 
C)  is not related to the equilibrium constant. 
D)  can be used to calculate whether a reaction is thermodynamically favorable under defined non-standard conditions. 
E)  can predict whether a reaction will be thermodynamically favorable under standard conditions. 
A)  will change if the temperature of the reaction is changed. 
B)  will change if the concentration of reactants and products are changed. 
C)  is not related to the equilibrium constant. 
D)  can be used to calculate whether a reaction is thermodynamically favorable under defined non-standard conditions. 
E)  can predict whether a reaction will be thermodynamically favorable under standard conditions.

Question 14

The standard reduction potentials for the following reactions are given below.
Pyruvate + 2H+ + 2e- → lactate E∘ = -0.190 V
NAD+ + 2H+ + 2e- → NADH/H+ E∘ = -0.320V.
Calculate △G∘ for the overall spontaneous reaction making use of the relationship between △E∘ and △G∘.

Accepted Answer

The answer of The standard reduction potentials for the following...

Question 15

Which of the following statements is FALSE?

Accepted Answer

A)  Organisms are open systems as they can exchange both energy and materials with their environments. 
B)  In an open system energy can be converted from one form into another. 
C)  Organisms are open systems as they can create energy from their environments. 
D)  Energy can be transferred between a system and the surroundings. 
E)  In biochemical processes, energy can neither be created or destroyed. 
A)  Organisms are open systems as they can exchange both energy and materials with their environments. 
B)  In an open system energy can be converted from one form into another. 
C)  Organisms are open systems as they can create energy from their environments. 
D)  Energy can be transferred between a system and the surroundings. 
E)  In biochemical processes, energy can neither be created or destroyed.

Question 16

The standard reduction potential is a measure of the ability of a reductant to ________ an electron.

Accepted Answer

The answer of The standard reduction potential is a measure...

Question 17

A thermodynamically unfavorable reaction can become favorable if the mass action ratio is ________ than the equilibrium mass action ratio.

Accepted Answer

The answer of A thermodynamically unfavorable reaction can become favorable...

Exam 3: The Energetics of Life

A reaction at its lowest energy state for the system and with equal rates in the forward and reverse directions is said to be at ________.

The change in enthalpy (△H) for the complete oxidation of a fatty acid is different depending on whether it occurs via a biochemical pathway or combustion to CO2 and H2O.

Calculate the △G∘' for the reaction fructose-6-phosphate → glucose-6-phosphate given the equilibrium constant is 1.97 and the physiological relevant temperature is 37∘C.

A reaction with a large negative free energy of hydrolysis can be coupled to the synthesis of ATP from ADP and Pi.

A reaction at equilibrium can be driven in one direction or the other by changing the ________ of reactants or products.

In a general redox reaction, the reductant becomes oxidized and the oxidant becomes reduced.

The equilibrium constant of a reaction:

Calculate the equilibrium constant for the enzymatic hydrolysis of 0.1 M glucose-6-phosphate to glucose and inorganic phosphate given that 0.05% of the original glucose-6-phosphate remained after reaching equilibrium and the activity of water is unity.

Life is an irreversible process, such that it never comes to equilibrium.

A thermodynamically unfavorable reaction can become favorable when coupled to a highly endergonic reaction.

A biochemical reaction will proceed in the direction as written if:

Which of the following statements is FALSE?

The △Go of a reaction:

The standard reduction potentials for the following reactions are given below. Pyruvate + 2H+ + 2e- → lactate E∘ = -0.190 V NAD+ + 2H+ + 2e- → NADH/H+ E∘ = -0.320V. Calculate △G∘ for the overall spontaneous reaction making use of the relationship between △E∘ and △G∘.

Which of the following statements is FALSE?

The standard reduction potential is a measure of the ability of a reductant to ________ an electron.

A thermodynamically unfavorable reaction can become favorable if the mass action ratio is ________ than the equilibrium mass action ratio.

Biochemistry and the Language of Chemistry

The Chemical Foundation of Life: Weak Interactions in an Aqueous Environment

Nucleic Acids

Introduction to Proteins: the Primary Level of Protein Structure

The Three-Dimensional Structure of Proteins

Protein Function and Evolution

Enzymes: Biological Catalysts

Carbohydrates: Sugars, Saccharides, Glycans

Lipids, Membranes, and Cellular Transport

Chemical Logic of Metabolism

Carbohydrate Metabolism: Glycolysis, Gluconeogenesis, Glycogen Metabolism, and the Pentose Phosphate Pathway

The Citric Acid Cycle

Electron Transport, Oxidative Phosphorylation, and Oxygen Metabolism

Photosynthesis

Lipid Metabolism

Interorgan and Intracellular Coordination of Energy Metabolism in Vertebrates

Amino Acid and Nitrogen Metabolism

Nucleotide Metabolism

Mechanisms of Signal Transduction

Genes, Genomes, and Chromosomes

DNA Replication

DNA Repair, Recombination, and Rearrangement

Transcription and Post-Transcriptional Processing

Information Decoding: Translation and Post-Translational Protein Processing

Regulation of Gene Expression

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