Question 1

Biochemists use a modified value for standard ΔG values because

Accepted Answer

A)  all reagents are not at a 1 molar concentration. 
B)  the pH in living systems is seldom, if ever, near 0. 
C)  the concentration of water is not at 1 molar concentration. 
D)  the reagents are not one molar and the pH = 7. 
E)  All of these justify why biochemists use a special ΔG value. 
A)  all reagents are not at a 1 molar concentration. 
B)  the pH in living systems is seldom, if ever, near 0. 
C)  the concentration of water is not at 1 molar concentration. 
D)  the reagents are not one molar and the pH = 7. 
E)  All of these justify why biochemists use a special ΔG value. B

Question 2

In biological redox reactions, hydrogen ions are usually transferred along with electrons.

Accepted Answer

A) True 
 B)False  True

Question 3

The number of degrees of freedom a molecule has is related to the numbers of resonant structures it has.

Accepted Answer

A) True 
 B)False  True

Question 4

The hydrolysis of ATP can be used to drive reactions that have a ΔG°' that is

Accepted Answer

A)  greater than +5 kJ/mol 
B)  less than +5 kJ/mol 
C)  between +20 and +40 kJ/mol 
D)  not possible to determine from the information in this chapter 
A)  greater than +5 kJ/mol 
B)  less than +5 kJ/mol 
C)  between +20 and +40 kJ/mol 
D)  not possible to determine from the information in this chapter

Question 5

What happens to the entropy when ATP is hydrolysed to ADP?

Accepted Answer

A)  Entropy increases 
B)  Entropy decreases. 
C)  Entropy doesn't change. 
D)  ATP has no entropy. 
A)  Entropy increases 
B)  Entropy decreases. 
C)  Entropy doesn't change. 
D)  ATP has no entropy.

Question 6

Consider this rxn which has a ΔG° = +0.4 kJ/mol. succinate + FAD ↔ fumarate + FADH2??1 mM of each compound are mixed & the reaction is allowed to come to equilibrium. Which statement is correct about the resulting concentration of FAD at equilibrium?

Accepted Answer

A)  [FAD] > [FADH2] 
B)  [FAD] 2] 
C)  [FAD] = [FADH2] 
D)  Cannot be determined from the information provided. 
A)  [FAD] > [FADH2] 
B)  [FAD] 2] 
C)  [FAD] = [FADH2] 
D)  Cannot be determined from the information provided.

Question 7

Consider this rxn which has a ΔG° = +0.4 kJ/mol. A + B ↔ C + D 1 M A, 1 M B, 0.1 M C and 0.1 M D are added to a container at room temperature. Which of the following statements is true?

Accepted Answer

A)  The reaction will proceed in the forward direction to reach equilibrium. 
B)  The reaction will proceed in the backward direction to reach equilibrium. 
C)  The reaction will not proceed in either direction; it is already at equilibrium. 
D)  Cannot be determined from the information provided. 
A)  The reaction will proceed in the forward direction to reach equilibrium. 
B)  The reaction will proceed in the backward direction to reach equilibrium. 
C)  The reaction will not proceed in either direction; it is already at equilibrium. 
D)  Cannot be determined from the information provided.

Question 8

The standard state of a solution is taken as

Accepted Answer

A)  1 atmosphere of pressure. 
B)  the pure solute. 
C)  1 molar concentration. 
D)  1 % by weight 
E)  none of the above. 
A)  1 atmosphere of pressure. 
B)  the pure solute. 
C)  1 molar concentration. 
D)  1 % by weight 
E)  none of the above.

Question 9

Many cells oxidize fatty acids to produce ATP. If no ATP were produced, the ΔG°' of this process would be

Accepted Answer

A)  unchanged 
B)  a larger positive number 
C)  a larger negative number 
D)  impossible to determine 
A)  unchanged 
B)  a larger positive number 
C)  a larger negative number 
D)  impossible to determine

Question 10

The linking of an exergonic reaction to drive an endergonic reaction is called:

Accepted Answer

A)  coupling 
B)  a state function 
C)  resonance 
D)  catabolsim 
A)  coupling 
B)  a state function 
C)  resonance 
D)  catabolsim

Question 11

Which of the following is not true concerning standard states?

Accepted Answer

A)  For pure liquids, the standard state is 1M 
B)  For pure solids, the standard state is the pure solid itself 
C)  For gases, the standard state is 1 atmosphere 
D)  For solutes, the standard state is 1M 
E)  All of the answers are true 
A)  For pure liquids, the standard state is 1M 
B)  For pure solids, the standard state is the pure solid itself 
C)  For gases, the standard state is 1 atmosphere 
D)  For solutes, the standard state is 1M 
E)  All of the answers are true

Question 12

Exhibit 15A Consider the reaction of alcohol dehydrogenase.
  
-Refer to Exhibit 15A. Which molecule is reduced?

Accepted Answer

A)  Ethanol 
B)  NAD+ 
C)  Acetaldehyde 
D)  NADH 
E)  H+ 
A)  Ethanol 
B)  NAD+ 
C)  Acetaldehyde 
D)  NADH 
E)  H+

Question 13

The efficiency of aerobic metabolism is greater than that of anaerobic metabolism even though much more energy is released in aerobic than in anaerobic metabolism because

Accepted Answer

A)  aerobic metabolism is linked to oxygen, which is a more powerful oxidizing agent than those in anaerobic metabolism 
B)  aerobic metabolism produces carbon dioxide and water 
C)  aerobic metabolism traps much more energy in the form of ATP than does anaerobic metabolism 
D)  anaerobic metabolism produces two- and three-carbon compounds 
A)  aerobic metabolism is linked to oxygen, which is a more powerful oxidizing agent than those in anaerobic metabolism 
B)  aerobic metabolism produces carbon dioxide and water 
C)  aerobic metabolism traps much more energy in the form of ATP than does anaerobic metabolism 
D)  anaerobic metabolism produces two- and three-carbon compounds

Question 14

Consider this rxn which has a ΔG° = +0.4 kJ/mol. A + B ↔ C + D 1 M A, 1 M B, 0.1 M C and 0.1 M D are added to a container at room temperature. Which of the following statements is true?

Accepted Answer

A)  ΔG  0 (i.e., it's positive) 
D)  Cannot be determined from the information provided. 
A)  ΔG  0 (i.e., it's positive) 
D)  Cannot be determined from the information provided.

Question 15

Metabolism takes place in stages

Accepted Answer

A)  because enzymes cannot catalyze the process efficiently 
B)  and allows for efficient production and use of energy 
C)  because large free energy changes cannot occur in living organisms 
D)  to use highly unreactive compounds 
A)  because enzymes cannot catalyze the process efficiently 
B)  and allows for efficient production and use of energy 
C)  because large free energy changes cannot occur in living organisms 
D)  to use highly unreactive compounds

Question 16

The oxidation of nutrients supplies the energy to produce ATP.

Accepted Answer

A) True 
 B)False

Question 17

"Metabolism" refers to

Accepted Answer

A)  the breakdown of larger molecules into smaller ones. 
B)  the production of larger molecules from smaller ones. 
C)  both of these 
D)  none of these 
A)  the breakdown of larger molecules into smaller ones. 
B)  the production of larger molecules from smaller ones. 
C)  both of these 
D)  none of these

Question 18

Consider these reactions: ATP → ADP + Pi
ΔG°' = −31 kJ/mol
Glucose-6-phosphate → glucose + Pi
ΔG°' = −13 kJ/mol
Glucose + ATP → glucose-6-phosphate + ADP
ΔG°' = ?
What is the ΔG°' of the last reaction?

Accepted Answer

A)  −44 kJ/mol 
B)  −18 kJ/mol 
C)  +18 kJ/mol 
D)  +44 kJ/mol 
E)  Cannot be determined from the information provided. 
A)  −44 kJ/mol 
B)  −18 kJ/mol 
C)  +18 kJ/mol 
D)  +44 kJ/mol 
E)  Cannot be determined from the information provided.

Question 19

Which of the following coenzymes is derived from riboflavin?

Accepted Answer

A)  Coenzyme A 
B)  NAD+. 
C)  FAD 
D)  All of the above. 
E)  None of the above. 
A)  Coenzyme A 
B)  NAD+. 
C)  FAD 
D)  All of the above. 
E)  None of the above.

Question 20

An oxidizing agent

Accepted Answer

A)  loses oxygen. 
B)  gains oxygen. 
C)  loses electrons. 
D)  gains electrons. 
A)  loses oxygen. 
B)  gains oxygen. 
C)  loses electrons. 
D)  gains electrons.

Exam 15: The Importance of Energy Changes and Electron Transfer in Metabolism

Biochemists use a modified value for standard ΔG values because

In biological redox reactions, hydrogen ions are usually transferred along with electrons.

The number of degrees of freedom a molecule has is related to the numbers of resonant structures it has.

The hydrolysis of ATP can be used to drive reactions that have a ΔG°' that is

What happens to the entropy when ATP is hydrolysed to ADP?

Consider this rxn which has a ΔG° = +0.4 kJ/mol. succinate + FAD ↔ fumarate + FADH2??1 mM of each compound are mixed & the reaction is allowed to come to equilibrium. Which statement is correct about the resulting concentration of FAD at equilibrium?

Consider this rxn which has a ΔG° = +0.4 kJ/mol. A + B ↔ C + D 1 M A, 1 M B, 0.1 M C and 0.1 M D are added to a container at room temperature. Which of the following statements is true?

The standard state of a solution is taken as

Many cells oxidize fatty acids to produce ATP. If no ATP were produced, the ΔG°' of this process would be

The linking of an exergonic reaction to drive an endergonic reaction is called:

Which of the following is not true concerning standard states?

Exhibit 15A Consider the reaction of alcohol dehydrogenase. -Refer to Exhibit 15A. Which molecule is reduced?

The efficiency of aerobic metabolism is greater than that of anaerobic metabolism even though much more energy is released in aerobic than in anaerobic metabolism because

Consider this rxn which has a ΔG° = +0.4 kJ/mol. A + B ↔ C + D 1 M A, 1 M B, 0.1 M C and 0.1 M D are added to a container at room temperature. Which of the following statements is true?

Metabolism takes place in stages

The oxidation of nutrients supplies the energy to produce ATP.

"Metabolism" refers to

Consider these reactions: ATP → ADP + Pi ΔG°' = −31 kJ/mol Glucose-6-phosphate → glucose + Pi ΔG°' = −13 kJ/mol Glucose + ATP → glucose-6-phosphate + ADP ΔG°' = ? What is the ΔG°' of the last reaction?

Which of the following coenzymes is derived from riboflavin?

An oxidizing agent

Biochemistry and the Organization of Cells

Water: the Solvent for Biochemical Reactions

Amino Acids and Peptides

The Three-Dimensional Structure of Proteins

Protein Purification and Characterization Techniques

The Behavior of Proteins: Enzymes

The Behavior of Proteins: Enzymes, Mechanisms, and Control

Lipids and Proteins Are Associated in Biological Membranes

Nucleic Acids: How Structure Conveys Information

Biosynthesis of Nucleic Acids: Replication

Transcription of the Genetic Code: Biosynthesis of RNA

Protein Synthesis: Translation of the Genetic Message

Nucleic Acid Biotechnology Techniques

Viruses, Cancer, and Immunology

Carbohydrates

Glycolysis

Storage Mechanisms and Control in Carbohydrate Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Lipid Metabolism

Photosynthesis

The Metabolism of Nitrogen

Integration of Metabolism: Cellular Signaling

Filters

Consider this rxn which has a ΔG° = +0.4 kJ/mol. succinate + FAD ↔ fumarate + FADH₂_??1 mM of each compound are mixed & the reaction is allowed to come to equilibrium. Which statement is correct about the resulting concentration of FAD at equilibrium?

Consider these reactions: ATP → ADP + P_i ΔG°' = −31 kJ/mol Glucose-6-phosphate → glucose + P_i ΔG°' = −13 kJ/mol Glucose + ATP → glucose-6-phosphate + ADP ΔG°' = ? What is the ΔG°' of the last reaction?