Question 1

Which of the following is NOT a chemical reason for the large negative ∆DG°' for the hydrolysis of ATP?

Accepted Answer

A) destabilization of the reactant due to bond strain caused by electrostatic repulsion 
B) the largely negative ∆S associated with it 
C) stabilization of the products by ionization and resonance 
D) entropy factors due to hydrolysis and subsequent ionization 
A) destabilization of the reactant due to bond strain caused by electrostatic repulsion 
B) the largely negative ∆S associated with it 
C) stabilization of the products by ionization and resonance 
D) entropy factors due to hydrolysis and subsequent ionization

Question 2

Which of these values is a widely used "consensus value" for ∆G°' of ATP hydrolysis in biological systems?

Accepted Answer

A) -2-30.5 kJ/mol 
B) -2-21 kJ/mol 
C) 3 kJ/mol 
D) 21 kJ/mol 
A) -2-30.5 kJ/mol 
B) -2-21 kJ/mol 
C) 3 kJ/mol 
D) 21 kJ/mol

Question 3

Given the following reaction,what can be said about the equilibrium concentrations of the components of the reaction? (Do not assume that concentrations began at standard conditions.)
Pyruvate + NADH + H?   lactate + NAD? ?G°' = -25.2 kJ/mol

Accepted Answer

A) [pyruvate][NADH] > [lactate][NAD?] [pyruvate]  [lactate] 
A) [pyruvate][NADH] > [lactate][NAD?] [pyruvate]  [lactate]

Question 4

Which thermodynamic property of a biochemical process is measured by calorimetry?

Accepted Answer

A) heat absorbed or given off,?H 
B) overall change in ?G° 
C) entropy change,?S 
D) volume change,?V 
A) heat absorbed or given off,?H 
B) overall change in ?G° 
C) entropy change,?S 
D) volume change,?V

Question 5

By which factor do equilibrium constants change for reactions coupled to ATP hydrolysis?

Accepted Answer

A) 102 
B) 104 
C) 106 
D) 108 
A) 102 
B) 104 
C) 106 
D) 108

Question 6

At what temperature is entropy,S,exactly zero?

Accepted Answer

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

Question 7

Which of these metabolites has a lower ∆G°' of hydrolysis than ATP?

Accepted Answer

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

Question 8

Based upon the following reactions,what would be the Based upon the following Based upon the following ?G°¢ for the formation of ATP from phosphoenolpyruvate and ADP?
ATP? ADP + Pi               ?G°' = -31.5 kJ/mol
Phosphoenolpyruvate? pyruvate + P??G°¢ = -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 
A) -93.7 kJ/mol 
B) -30.7 kJ/mol 
C) +30.7 kJ/mol 
D) +93.7 kJ/mol

Question 9

Which energy source does virtually all life on earth depend on?

Accepted Answer

A) activation energy 
B) batteries 
C) the green-house effect 
D) the sun 
A) activation energy 
B) batteries 
C) the green-house effect 
D) the sun

Question 10

Which of the following characteristics does NOT apply to internal energy?

Accepted Answer

A) It includes all the energy that might be exchanged in physical or chemical processes. 
B) It is path dependent. 
C) It is referred to as a state function. 
D) It is commonly designated E or U. 
A) It includes all the energy that might be exchanged in physical or chemical processes. 
B) It is path dependent. 
C) It is referred to as a state function. 
D) It is commonly designated E or U.

Question 11

Which of the following is NOT correct regarding ∆G?

Accepted Answer

A) ∆G depends upon the concentration of the reactants and products. 
B) ∆G is affected by temperature. 
C) ∆G is negative for endergonic reactions. 
D) ∆G is affected by pressure and pH. 
A) ∆G depends upon the concentration of the reactants and products. 
B) ∆G is affected by temperature. 
C) ∆G is negative for endergonic reactions. 
D) ∆G is affected by pressure and pH.

Question 12

Which of the following is correct regarding basic systems?

Accepted Answer

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

Question 13

Which of the following is a characteristic of ATP?

Accepted Answer

A) The energy of hydrolysis is the same for all of the phosphate groups of the molecule. 
B) ATP does not hydrolyze spontaneously due to a very high activation energy. 
C) The ∆G of hydrolysis within the cell is substantially greater than the ∆G°¢ 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. 
A) The energy of hydrolysis is the same for all of the phosphate groups of the molecule. 
B) ATP does not hydrolyze spontaneously due to a very high activation energy. 
C) The ∆G of hydrolysis within the cell is substantially greater than the ∆G°¢ 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.

Question 14

What defines the standard-state free energy change,∆G?

Accepted Answer

A) positive when the reaction is unfavourable 
B) an expression of Keq 
C) negative when the reaction is favourable 
D) equal to ∆H - T∆S 
A) positive when the reaction is unfavourable 
B) an expression of Keq 
C) negative when the reaction is favourable 
D) equal to ∆H - T∆S

Question 15

Which pairs of biomolecules mediate the flow of energy from exergonic reactions to the energy-requiring processes of life?

Accepted Answer

A) reduced coenzymes and high-energy phosphate compounds 
B) high-energy phosphate compounds and caffeine 
C) chlorophyll and caffeine 
D) hemoglobin and chlorophyll 
A) reduced coenzymes and high-energy phosphate compounds 
B) high-energy phosphate compounds and caffeine 
C) chlorophyll and caffeine 
D) hemoglobin and chlorophyll

Exam 3: Thermodynamics of Biological Systems

Which of the following is NOT a chemical reason for the large negative ∆DG°' for the hydrolysis of ATP?

Which of these values is a widely used "consensus value" for ∆G°' of ATP hydrolysis in biological systems?

Given the following reaction,what can be said about the equilibrium concentrations of the components of the reaction? (Do not assume that concentrations began at standard conditions.) Pyruvate + NADH + H? lactate + NAD? ?G°' = -25.2 kJ/mol

Which thermodynamic property of a biochemical process is measured by calorimetry?

By which factor do equilibrium constants change for reactions coupled to ATP hydrolysis?

At what temperature is entropy,S,exactly zero?

Which of these metabolites has a lower ∆G°' of hydrolysis than ATP?

Based upon the following reactions,what would be the Based upon the following Based upon the following ?G°¢ for the formation of ATP from phosphoenolpyruvate and ADP? ATP? ADP + Pi ?G°' = -31.5 kJ/mol Phosphoenolpyruvate? pyruvate + P??G°¢ = -62.2 kJ/mol

Which energy source does virtually all life on earth depend on?

Which of the following characteristics does NOT apply to internal energy?

Which of the following is NOT correct regarding ∆G?

Which of the following is correct regarding basic systems?

Which of the following is a characteristic of ATP?

What defines the standard-state free energy change,∆G?

Which pairs of biomolecules mediate the flow of energy from exergonic reactions to the energy-requiring processes of life?

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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