Question 1

Which of the following statements regarding ATP is true?

Accepted Answer

A)  the energy of hydrolysis is the same for all of the phosphate groups of the molecule 
B)  despite the very exergonic nature of the hydrolysis, ATP does not hydrolyze spontaneously due to a very high activation energy 
C)  the ΔG of hydrolysis within the cell is substantially greater than the ΔG°′ due to a higher concentration of ATP with respect to ADP 
D)  electrostatic attraction of the phosphate groups contributes to a more exergonic free energy 
E)  both b and c are correct 
A)  the energy of hydrolysis is the same for all of the phosphate groups of the molecule 
B)  despite the very exergonic nature of the hydrolysis, ATP does not hydrolyze spontaneously due to a very high activation energy 
C)  the ΔG of hydrolysis within the cell is substantially greater than the ΔG°′ due to a higher concentration of ATP with respect to ADP 
D)  electrostatic attraction of the phosphate groups contributes to a more exergonic free energy 
E)  both b and c are correct B

Question 2

Which statement pertaining to the three basic systems is true?

Accepted Answer

A)  The internal energy of an isolated system is mostly conserved. 
B)  Open systems can exchange matter with other open systems. 
C)  Open systems can exchange matter with a closed system. 
D)  The internal energy of an open system is always constant. 
E)  A closed system can accept heat from an isolated system. 
A)  The internal energy of an isolated system is mostly conserved. 
B)  Open systems can exchange matter with other open systems. 
C)  Open systems can exchange matter with a closed system. 
D)  The internal energy of an open system is always constant. 
E)  A closed system can accept heat from an isolated system. B

Question 3

Living systems are:

Accepted Answer

A)  closed systems exchanging only energy with the surroundings. 
B)  isolated systems that are totally contained. 
C)  open systems exchanging only energy with the surroundings. 
D)  open systems exchanging both energy and matter with their surroundings. 
E)  none of the above. 
A)  closed systems exchanging only energy with the surroundings. 
B)  isolated systems that are totally contained. 
C)  open systems exchanging only energy with the surroundings. 
D)  open systems exchanging both energy and matter with their surroundings. 
E)  none of the above. D

Question 4

The effects of ____ on the ΔG°′ of hydrolysis of ATP are much greater than the effects of ____ or ____ under physiological conditions.

Accepted Answer

A)  pH, concentration, metal ions 
B)  metal ions, pH, concentration 
C)  temperature, concentration, pH 
D)  concentration, pH, metal ions 
E)  none of the above. 
A)  pH, concentration, metal ions 
B)  metal ions, pH, concentration 
C)  temperature, concentration, pH 
D)  concentration, pH, metal ions 
E)  none of the above.

Question 5

The hydrolysis of a phosphate from which of the following molecules is most thermodynamically favorable?

Accepted Answer

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

Question 6

Which of the following statements about ATP is NOT true?

Accepted Answer

A)  It is used for short-term energy in the cell. 
B)  It has two phosphoanhydride bonds. 
C)  The reason for the large −ΔG° values of hydrolysis reactions is due to stabilization of products. 
D)  ATP is usually complexed with Mn2+. 
E)  ATP is a kinetically stable molecule. 
A)  It is used for short-term energy in the cell. 
B)  It has two phosphoanhydride bonds. 
C)  The reason for the large −ΔG° values of hydrolysis reactions is due to stabilization of products. 
D)  ATP is usually complexed with Mn2+. 
E)  ATP is a kinetically stable molecule.

Question 7

The chemical reasons for the large negative ΔG°′ for the hydrolysis of ____ include destabilization of the reactant due to bond strain caused by electrostatic repulsion, stabilization of the products by ionization and resonance, and entropy factors due to hydrolysis and subsequent ionization.

Accepted Answer

A)  AMP 
B)  ATP 
C)  PEP 
D)  Phosphocreatine 
E)  All of the above 
A)  AMP 
B)  ATP 
C)  PEP 
D)  Phosphocreatine 
E)  All of the above

Question 8

Virtually all life on earth depends on energy ULTIMATELY from:

Accepted Answer

A)  the power company. 
B)  batteries. 
C)  the green-house effect. 
D)  the sun. 
E)  activation energy. 
A)  the power company. 
B)  batteries. 
C)  the green-house effect. 
D)  the sun. 
E)  activation energy.

Question 9

Based upon the following reactions, what would be the ΔG°′ for the formation of ATP from phosphoenolpyruvate and ADP?
ATP → ADP + Pi
ΔG°′ = −31.5 kJ/mol
Phosphoenolpyruvate → pyruvate + Pi
ΔG°′ = −62.2 kJ/mol

Accepted Answer

A)  −93.7 kJ/mol 
B)  −30.7 kJ/mol 
C)  +30.7 kJ/mol 
D)  +93.7 kJ/mol 
E)  cannot determine from given information 
A)  −93.7 kJ/mol 
B)  −30.7 kJ/mol 
C)  +30.7 kJ/mol 
D)  +93.7 kJ/mol 
E)  cannot determine from given information

Question 10

Biochemists define the group transfer potential as the ____ that occurs upon hydrolysis (i.e., transfer of the particular group to water).

Accepted Answer

A)  ΔG 
B)  ΔH 
C)  ΔS 
D)  ΔCp 
E)  ΔE 
A)  ΔG 
B)  ΔH 
C)  ΔS 
D)  ΔCp 
E)  ΔE

Question 11

Which statement MOST COMPLETELY EXPLAINS the large ΔG° for the hydrolysis of phosphoenolpyruvate?

Accepted Answer

A)  Hydrolysis of the phosphate 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. 
E)  The large ΔG° of the phosphoester bond. 
A)  Hydrolysis of the phosphate 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. 
E)  The large ΔG° of the phosphoester bond.

Question 12

All are true about ΔG EXCEPT?

Accepted Answer

A)  A positive or negative ΔG tells us which direction the reaction will proceed. 
B)  ΔG depends upon the concentration of the reactants and products. 
C)  ΔG is affected by temperature. 
D)  ΔG is affected by pressure and pH. 
E)  ΔG is negative for endergonic reactions. 
A)  A positive or negative ΔG tells us which direction the reaction will proceed. 
B)  ΔG depends upon the concentration of the reactants and products. 
C)  ΔG is affected by temperature. 
D)  ΔG is affected by pressure and pH. 
E)  ΔG is negative for endergonic reactions.

Question 13

Enthalpy change, ΔH, is:

Accepted Answer

A)  the sum of heat absorbed and work. 
B)  not a thermodynamic state function. 
C)  a measure of disorder in a system. 
D)  determined by pressure change at a constant temperature. 
E)  equal to the heat transferred at constant pressure and volume. 
A)  the sum of heat absorbed and work. 
B)  not a thermodynamic state function. 
C)  a measure of disorder in a system. 
D)  determined by pressure change at a constant temperature. 
E)  equal to the heat transferred at constant pressure and volume.

Question 14

To predict whether pairs of coupled reactions will proceed spontaneously:

Accepted Answer

A)  Subtract the smaller from the larger ΔG. 
B)  Sum the ΔG°′ values for each reaction. 
C)  Add the ΔS values for each reaction at constant temperature. 
D)  The absolute value of the positive ΔG°′ must be larger than the value of the negative ΔG°′. 
E)  None are true. 
A)  Subtract the smaller from the larger ΔG. 
B)  Sum the ΔG°′ values for each reaction. 
C)  Add the ΔS values for each reaction at constant temperature. 
D)  The absolute value of the positive ΔG°′ must be larger than the value of the negative ΔG°′. 
E)  None are true.

Question 15

Entropy, S, is exactly zero at:

Accepted Answer

A)  25°C 
B)  0°C 
C)  25°K 
D)  0°K 
E)  38°C 
A)  25°C 
B)  0°C 
C)  25°K 
D)  0°K 
E)  38°C

Question 16

"High-energy" compounds exhibit large negative free energy of hydrolysis and include all EXCEPT:

Accepted Answer

A)  phosphate esters. 
B)  enol phosphates. 
C)  acyl phosphates. 
D)  guanidino phosphates. 
E)  thioesters. 
A)  phosphate esters. 
B)  enol phosphates. 
C)  acyl phosphates. 
D)  guanidino phosphates. 
E)  thioesters.

Question 17

A widely used "consensus value" for ΔG°′ of ATP hydrolysis in biological systems is ____ kJ/mol.

Accepted Answer

A)  −21 
B)  −30.5 
C)  −7 
D)  3 
E)  21 
A)  −21 
B)  −30.5 
C)  −7 
D)  3 
E)  21

Question 18

​Discuss the relationship between the Gibbs free energy (G°') of adenosine triphosphate (ATP) hydrolysis and Mg2+ concentration, and how this relationship is affected by pH.

Accepted Answer

Mg²⁺ binds strongly to the triphosphate ox

Question 19

Define the three state functions that describe the energetics of biochemical reactions. Write the relationship between the three state functions.​

Accepted Answer

The three state functions are as follows

Question 20

The metabolite with a lower ΔG°′ of hydrolysis than ATP is:

Accepted Answer

A)  acetyl phosphate. 
B)  phosphoenol pyruvate (PEP). 
C)  phosphocreatine. 
D)  adenosine-5'-phosphate. 
E)  pyrophosphate. 
A)  acetyl phosphate. 
B)  phosphoenol pyruvate (PEP). 
C)  phosphocreatine. 
D)  adenosine-5'-phosphate. 
E)  pyrophosphate.

Exam 3: Thermodynamics of Biological Systems

Which of the following statements regarding ATP is true?

Which statement pertaining to the three basic systems is true?

Living systems are:

The effects of ____ on the ΔG°′ of hydrolysis of ATP are much greater than the effects of ____ or ____ under physiological conditions.

The hydrolysis of a phosphate from which of the following molecules is most thermodynamically favorable?

Which of the following statements about ATP is NOT true?

The chemical reasons for the large negative ΔG°′ for the hydrolysis of ____ include destabilization of the reactant due to bond strain caused by electrostatic repulsion, stabilization of the products by ionization and resonance, and entropy factors due to hydrolysis and subsequent ionization.

Virtually all life on earth depends on energy ULTIMATELY from:

Based upon the following reactions, what would be the ΔG°′ for the formation of ATP from phosphoenolpyruvate and ADP? ATP → ADP + Pi ΔG°′ = −31.5 kJ/mol Phosphoenolpyruvate → pyruvate + Pi ΔG°′ = −62.2 kJ/mol

Biochemists define the group transfer potential as the ____ that occurs upon hydrolysis (i.e., transfer of the particular group to water).

Which statement MOST COMPLETELY EXPLAINS the large ΔG° for the hydrolysis of phosphoenolpyruvate?

All are true about ΔG EXCEPT?

Enthalpy change, ΔH, is:

To predict whether pairs of coupled reactions will proceed spontaneously:

Entropy, S, is exactly zero at:

"High-energy" compounds exhibit large negative free energy of hydrolysis and include all EXCEPT:

A widely used "consensus value" for ΔG°′ of ATP hydrolysis in biological systems is ____ kJ/mol.

​Discuss the relationship between the Gibbs free energy (G°') of adenosine triphosphate (ATP) hydrolysis and Mg2+ concentration, and how this relationship is affected by pH.

Define the three state functions that describe the energetics of biochemical reactions. Write the relationship between the three state functions.​

The metabolite with a lower ΔG°′ of hydrolysis than ATP is:

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

Water: the Medium of Life

Amino Acids and the Peptide Bond

Proteins: Their Primary Structure and Biological Functions

Proteins: Secondary, Tertiary, and Quaternary Structure

Carbohydrates and the Glycoconjugates of Cell Surfaces

Lipids

Membranes and Membrane Transport

Nucleotides and Nucleic Acids

Structure of Nucleic Acids

Recombinant Dna, Cloning, Chimeric Genes, and Synthetic Biology

Enzymeskinetics and Specificity

Mechanisms of Enzyme Action

Enzyme Regulation

Molecular Motors

Metabolism: an Overview

Glycolysis

The Tricarboxylic Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Gluconeogenesis, Glycogen Metabolism, and the Pentose Phosphate Pathway

Fatty Acid Catabolism

Lipid Biosynthesis

Nitrogen Acquisition and Amino Acid Metabolism

Synthesis and Degradation of Nucleotides

Metabolic Integration and Organ Specialization

Dna Metabolism: Replication, Recombination, and Repair

Transcription and the Regulation of Gene Expression

Protein Synthesis

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

The Reception and Transmission of Extracellular Information

Filters

The effects of on the ΔG°′ of hydrolysis of ATP are much greater than the effects of or under physiological conditions.

Discuss the relationship between the Gibbs free energy (G°') of adenosine triphosphate (ATP) hydrolysis and Mg²⁺ concentration, and how this relationship is affected by pH.

Define the three state functions that describe the energetics of biochemical reactions. Write the relationship between the three state functions.