Question 1

Which statement best explains the large ∆G° for the hydrolysis of phosphoenolpyruvate?

Accepted Answer

A) hydrolysis of the phosphoanhydride bond along with the conversion of the enol to the keto form of pyruvate 
B) the hydrolysis of the phosphoanhydride bond 
C) conversion from the enol to the keto form of pyruvate 
D) strong bond energy along with a change in the stereochemistry of the molecule 
A) hydrolysis of the phosphoanhydride bond along with the conversion of the enol to the keto form of pyruvate 
B) the hydrolysis of the phosphoanhydride bond 
C) conversion from the enol to the keto form of pyruvate 
D) strong bond energy along with a change in the stereochemistry of the molecule A

Question 2

Which of the following does NOT describe a modified standard state for a thermodynamic parameter?

Accepted Answer

A) designated with a prime ( ' )symbol 
B) H⁺ ion of 1 M 
C) 1 M for solutions 
D) when the solvent is water at pH = 7 
A) designated with a prime ( ' )symbol 
B) H⁺ ion of 1 M 
C) 1 M for solutions 
D) when the solvent is water at pH = 7 B

Question 3

Which example has the greatest increase in entropy,∆S?

Accepted Answer

A) freezing water 
B) sublimation of CO₂ 
C) melting ice 
D) boiling gasoline 
A) freezing water 
B) sublimation of CO₂ 
C) melting ice 
D) boiling gasoline B

Question 4

Which of the following is NOT a feature of thermodynamics?

Accepted Answer

A) It describes the flow and interchange of heat,energy,and matter. 
B) It allows the determination of whether a reaction is spontaneous. 
C) It provides information on the rate of a reaction. 
D) It considers heat flow and entropy production. 
A) It describes the flow and interchange of heat,energy,and matter. 
B) It allows the determination of whether a reaction is spontaneous. 
C) It provides information on the rate of a reaction. 
D) It considers heat flow and entropy production.

Question 5

What defines entropy change,∆S?

Accepted Answer

A) the sum of heat absorbed and work 
B) equal to the heat transferred at constant pressure and volume 
C) a measure of disorder in a system 
D) pressure change at a constant temperature 
A) the sum of heat absorbed and work 
B) equal to the heat transferred at constant pressure and volume 
C) a measure of disorder in a system 
D) pressure change at a constant temperature

Question 6

Which equation defines a system at equilibrium?

Accepted Answer

A) ∆G > 0 
B) ∆G° = ∆G 
C) ∆G = 0 
D) ∆G° = 0 
E) ∆G = RT ln ([products]/[reactants]) 
A) ∆G > 0 
B) ∆G° = ∆G 
C) ∆G = 0 
D) ∆G° = 0 
E) ∆G = RT ln ([products]/[reactants])

Question 7

Thermodynamic parameters (entropy,enthalpy,free energy,and internal energy)are given for an unknown enzyme.What result is expected for the breaking of hydrogen bonds and the exposure of hydrophobic groups from the interior during the unfolding process of a protein?

Accepted Answer

A) Entropy change,∆S,is zero. 
B) Enthalpy change,∆H,is positive. 
C) Entropy change,∆S,is positive. 
D) Enthalpy change,∆H,is negative. 
A) Entropy change,∆S,is zero. 
B) Enthalpy change,∆H,is positive. 
C) Entropy change,∆S,is positive. 
D) Enthalpy change,∆H,is negative.

Question 8

Which of the following factors has the greatest effect on the ∆G°' of hydrolysis of ATP?

Accepted Answer

A) concentration 
B) metal ions 
C) temperature 
D) pH 
A) concentration 
B) metal ions 
C) temperature 
D) pH

Question 9

From which of the following molecules is the hydrolysis of a phosphate most thermodynamically favourable?

Accepted Answer

A) adenosine-5'-triphosphate 
B) glucose phosphate 
C) adenosine-5'-diphosphate 
D) phosphoenolpyruvate 
A) adenosine-5'-triphosphate 
B) glucose phosphate 
C) adenosine-5'-diphosphate 
D) phosphoenolpyruvate

Question 10

An interaction between 2 subunits of a protein was determined to have a ?G°'= -57.05 kJ/mol.What is the K?q for the reaction at 25°C?

Accepted Answer

A) 10-10 
B) 1.02 
C) 1.32 
D) 1010 
A) 10-10 
B) 1.02 
C) 1.32 
D) 1010

Question 11

"High-energy" compounds exhibit large negative free energy of hydrolysis.Which of the following are NOT "high-energy" compounds?

Accepted Answer

A) phosphate esters 
B) enol phosphates and phosphate anhydrides 
C) acyl phosphates 
D) guanidino phosphates 
A) phosphate esters 
B) enol phosphates and phosphate anhydrides 
C) acyl phosphates 
D) guanidino phosphates

Question 12

Which of the following best describes living systems?

Accepted Answer

A) They are closed systems exchanging only energy with the surroundings. 
B) They are isolated systems that are totally contained. 
C) They are open systems exchanging only energy with the surroundings. 
D) They are open systems exchanging both energy and matter with their surroundings. 
A) They are closed systems exchanging only energy with the surroundings. 
B) They are isolated systems that are totally contained. 
C) They are open systems exchanging only energy with the surroundings. 
D) They are open systems exchanging both energy and matter with their surroundings.

Question 13

Which of the following is correct for a spontaneous endothermic reaction?

Accepted Answer

A) Heat must be given off by the reaction. 
B) Energy must be added to the reaction. 
C) The temperature must be very low. 
D) The entropy must increase substantially. 
A) Heat must be given off by the reaction. 
B) Energy must be added to the reaction. 
C) The temperature must be very low. 
D) The entropy must increase substantially.

Question 14

Which of the following is NOT a feature of ATP?

Accepted Answer

A) It is used for short-term energy in the cell. 
B) It has 2 phosphoanhydride bonds. 
C) It is usually complexed with Ca²⁺. 
D) It is a kinetically stable molecule. 
A) It is used for short-term energy in the cell. 
B) It has 2 phosphoanhydride bonds. 
C) It is usually complexed with Ca²⁺. 
D) It is a kinetically stable molecule.

Question 15

Which of the following is NOT a feature of the second law of thermodynamics?

Accepted Answer

A) Systems tend to proceed from ordered states to disordered states. 
B) The entropy of the system plus surroundings is unchanged by reversible processes. 
C) The entropy of the system plus surroundings increases for irreversible processes. 
D) All naturally occurring processes proceed toward equilibrium. 
A) Systems tend to proceed from ordered states to disordered states. 
B) The entropy of the system plus surroundings is unchanged by reversible processes. 
C) The entropy of the system plus surroundings increases for irreversible processes. 
D) All naturally occurring processes proceed toward equilibrium.

Question 16

Which of the following is an example of an open system?

Accepted Answer

A) a chemical reaction taking place in a closed beaker 
B) a steam radiator 
C) an insulated bomb reactor 
D) a pot of boiling water 
A) a chemical reaction taking place in a closed beaker 
B) a steam radiator 
C) an insulated bomb reactor 
D) a pot of boiling water

Question 17

How can pairs of spontaneously coupled reactions be predicted?

Accepted Answer

A) by subtracting the smaller from the larger ∆G 
B) by summing the ∆G°s for each reaction 
C) by adding the ∆S values for each reaction at constant temperature 
D) by determining if the absolute value of the positive ∆G°' must be larger than the value of the negative ∆G°' 
A) by subtracting the smaller from the larger ∆G 
B) by summing the ∆G°s for each reaction 
C) by adding the ∆S values for each reaction at constant temperature 
D) by determining if the absolute value of the positive ∆G°' must be larger than the value of the negative ∆G°'

Question 18

What defines enthalpy change,∆H?

Accepted Answer

A) It is the sum of heat absorbed and work. 
B) It is a measure of disorder in a system. 
C) It is equal to the heat transferred at constant pressure and volume. 
D) It is determined by pressure change at a constant temperature. 
A) It is the sum of heat absorbed and work. 
B) It is a measure of disorder in a system. 
C) It is equal to the heat transferred at constant pressure and volume. 
D) It is determined by pressure change at a constant temperature.

Question 19

Which of the following can ADP accept from higher energy molecules,while ATP can donate to lower energy molecules of metabolism?

Accepted Answer

A) phosphates 
B) reactants 
C) products 
D) energy 
A) phosphates 
B) reactants 
C) products 
D) energy

Question 20

Which thermodynamic property defines the group transfer potential that occurs upon hydrolysis (i.e.,transfer of the particular group to water)?

Accepted Answer

A) ∆G 
B) ∆H 
C) ∆S 
D) ∆E 
A) ∆G 
B) ∆H 
C) ∆S 
D) ∆E

Exam 3: Thermodynamics of Biological Systems

Which statement best explains the large ∆G° for the hydrolysis of phosphoenolpyruvate?

Which of the following does NOT describe a modified standard state for a thermodynamic parameter?

Which example has the greatest increase in entropy,∆S?

Which of the following is NOT a feature of thermodynamics?

What defines entropy change,∆S?

Which equation defines a system at equilibrium?

Thermodynamic parameters (entropy,enthalpy,free energy,and internal energy)are given for an unknown enzyme.What result is expected for the breaking of hydrogen bonds and the exposure of hydrophobic groups from the interior during the unfolding process of a protein?

Which of the following factors has the greatest effect on the ∆G°' of hydrolysis of ATP?

From which of the following molecules is the hydrolysis of a phosphate most thermodynamically favourable?

An interaction between 2 subunits of a protein was determined to have a ?G°'= -57.05 kJ/mol.What is the K?q for the reaction at 25°C?

"High-energy" compounds exhibit large negative free energy of hydrolysis.Which of the following are NOT "high-energy" compounds?

Which of the following best describes living systems?

Which of the following is correct for a spontaneous endothermic reaction?

Which of the following is NOT a feature of ATP?

Which of the following is NOT a feature of the second law of thermodynamics?

Which of the following is an example of an open system?

How can pairs of spontaneously coupled reactions be predicted?

What defines enthalpy change,∆H?

Which of the following can ADP accept from higher energy molecules,while ATP can donate to lower energy molecules of metabolism?

Which thermodynamic property defines the group transfer potential that occurs upon hydrolysis (i.e.,transfer of the particular group to water)?

The Facts of Life: Chemistry Is the Logic of Biological Phenomena

Water: the Medium of Life

Amino Acids

Proteins: Their Primary Structure and Biological Functions

Proteins: Secondary, tertiary, and Quaternary Structure

Carbohydrates and the Glycoconjugates of Cell Surfaces

Lipids

Lipid Biosynthesis

Membranes and Membrane Transport

The Reception and Transmission of Extracellular Information

Enzymes Kinetics and Specificity

Mechanisms of Enzyme Action

Enzyme Regulation

Molecular Motors

Nutrition and the Organization of Metabolism

Glycolysis

The Tricarboxylic Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Gluconeogenesis, glycogen Metabolism, and the Pentose Phosphate Pathway

Fatty Acid Catabolism

Nitrogen Acquisition and Amino Acid Metabolism

Nucleotides and Nucleic Acids

Structure of Nucleic Acids

Synthesis and Degradation of Nucleotides

Recombinant Dna: Cloning and Creation of Chimeric Genes

DNA Metabolism: Replication, recombination, and Repair

Transcription and the Regulation of Gene Expression

Protein Synthesis

Post-Transcriptional Regulation of Gene Expression

Completing the Protein Life Cycle: Folding, processing, and Degradation

Metabolic Integration and Organ Specialization

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