Question 1

The final reduced species in the electron transport chain is

Accepted Answer

A)  O2 
B)  H2O 
C)  cytochrome c 
D)  coenzyme Q 
E)  none of these 
A)  O2 
B)  H2O 
C)  cytochrome c 
D)  coenzyme Q 
E)  none of these B

Question 2

Which of the following is true?

Accepted Answer

A)  Uncoupling agents can work by disrupting the flow of protons during ATP synthesis. 
B)  Uncoupling agents prevent the flow of electrons during electron transport 
C)  Uncoupling agents always block the flow of protons through the ATPase 
D)  none of these is true 
A)  Uncoupling agents can work by disrupting the flow of protons during ATP synthesis. 
B)  Uncoupling agents prevent the flow of electrons during electron transport 
C)  Uncoupling agents always block the flow of protons through the ATPase 
D)  none of these is true A

Question 3

A species in the electron transport chain that can participate in a two-electron transfer is

Accepted Answer

A)  iron-sulfur proteins. 
B)  cytochrome b. 
C)  cytochrome c. 
D)  coenzyme Q. 
A)  iron-sulfur proteins. 
B)  cytochrome b. 
C)  cytochrome c. 
D)  coenzyme Q. D

Question 4

Creatine supplements work best for long distance exercise, rather than for quick spurts of energy.

Accepted Answer

A) True 
 B)False

Question 5

The only complex which actually uses molecular oxygen is

Accepted Answer

A)  Complex I. 
B)  Complex II. 
C)  Complex III. 
D)  Complex IV. 
E)  It is not known where oxygen is used. 
A)  Complex I. 
B)  Complex II. 
C)  Complex III. 
D)  Complex IV. 
E)  It is not known where oxygen is used.

Question 6

The Q cycle refers to flow of electrons from

Accepted Answer

A)  NADH to coenzyme Q via Complex I. 
B)  FADH2 to coenzyme Q via Complex II. 
C)  coenzyme Q to cytochrome c via Complex III. 
D)  coenzyme Q to NADH. 
E)  none of these 
A)  NADH to coenzyme Q via Complex I. 
B)  FADH2 to coenzyme Q via Complex II. 
C)  coenzyme Q to cytochrome c via Complex III. 
D)  coenzyme Q to NADH. 
E)  none of these

Question 7

The F1F0 complex is actually a transmembrane complex.

Accepted Answer

A) True 
 B)False

Question 8

Chemiosmotic coupling involves this process:

Accepted Answer

A)  Using an electron gradient to synthesize ATP. 
B)  Using a proton gradient to synthesize ATP. 
C)  Using oxygen flow to synthesize ATP. 
D)  Using a proton gradient to make water from oxygen. 
E)  These are all chemiosmotic processes. 
A)  Using an electron gradient to synthesize ATP. 
B)  Using a proton gradient to synthesize ATP. 
C)  Using oxygen flow to synthesize ATP. 
D)  Using a proton gradient to make water from oxygen. 
E)  These are all chemiosmotic processes.

Question 9

The reference reaction for determining reduction potentials (E° = 0) is the reduction of

Accepted Answer

A)  oxygen (O2) to water. 
B)  NAD+ to NADH. 
C)  H+ to H2 gas. 
D)  FAD to FADH2. 
E)  none of these 
A)  oxygen (O2) to water. 
B)  NAD+ to NADH. 
C)  H+ to H2 gas. 
D)  FAD to FADH2. 
E)  none of these

Question 10

Which of the following procedures is most unique to the determination of the order of the passage of electrons through the electron transport chain was determined

Accepted Answer

A)  use of respiratory inhibitors 
B)  spectroscopy 
C)  isolation of intact mitochondria 
D)  none of these have anything to do with determining the order 
A)  use of respiratory inhibitors 
B)  spectroscopy 
C)  isolation of intact mitochondria 
D)  none of these have anything to do with determining the order

Question 11

Oxidative phosphorylation is coupled to electron transport in

Accepted Answer

A)  Complexes I, II, and III 
B)  Complexes I, II, and IV 
C)  Complexes I, III, and IV 
D)  all four respiratory complexes 
A)  Complexes I, II, and III 
B)  Complexes I, II, and IV 
C)  Complexes I, III, and IV 
D)  all four respiratory complexes

Question 12

What is the net yield of ATP per glucose molecule that passes through all of aerobic respiration (glucose → CO2 + H2O)?

Accepted Answer

A)  2 
B)  4 
C)  6 
D)  30 − 32, dependent on the shuttle system used. 
A)  2 
B)  4 
C)  6 
D)  30 − 32, dependent on the shuttle system used.

Question 13

Electron flow in the mitochondria follows this pathway:

Accepted Answer

A)  Complex I → complex II → complex III → complex IV. 
B)  Complex IV → complex III → complex II → complex I. 
C)  Complex I → complex III → complex IV. 
D)  Complex II → complex III → complex IV. 
E)  Both complex I → III → IV and complex II → III → IV. 
A)  Complex I → complex II → complex III → complex IV. 
B)  Complex IV → complex III → complex II → complex I. 
C)  Complex I → complex III → complex IV. 
D)  Complex II → complex III → complex IV. 
E)  Both complex I → III → IV and complex II → III → IV.

Question 14

Which of the following statements concerning E° for an electron-transfer reaction is false?

Accepted Answer

A)  It is measured by comparison with the partial pressure of oxygen in the bloodstream rather than 1 atmosphere pressure. 
B)  It is measured by comparison with a standard hydrogen electrode. 
C)  It is related to ΔG° by a well known equation. 
D)  It cannot be determined for electron-transfer reactions involving coenzyme Q. 
A)  It is measured by comparison with the partial pressure of oxygen in the bloodstream rather than 1 atmosphere pressure. 
B)  It is measured by comparison with a standard hydrogen electrode. 
C)  It is related to ΔG° by a well known equation. 
D)  It cannot be determined for electron-transfer reactions involving coenzyme Q.

Question 15

Which of the following is not a part of the electron transport chain?

Accepted Answer

A)  NADH 
B)  FADH2 
C)  coenzyme Q 
D)  coenzyme A 
A)  NADH 
B)  FADH2 
C)  coenzyme Q 
D)  coenzyme A

Question 16

Most of the reactions of electron transport in the mitochondria occur

Accepted Answer

A)  on the outer membrane 
B)  on the inner membrane. 
C)  in the mitochondrial matrix. 
D)  in the intermembrane space. 
E)  in the cytosol. 
A)  on the outer membrane 
B)  on the inner membrane. 
C)  in the mitochondrial matrix. 
D)  in the intermembrane space. 
E)  in the cytosol.

Question 17

Which complex contains cytochrome oxidase?

Accepted Answer

A)  Complex I 
B)  Complex II 
C)  Complex III 
D)  Complex IV 
E)  It is not known where cytochrome oxidase is located. 
A)  Complex I 
B)  Complex II 
C)  Complex III 
D)  Complex IV 
E)  It is not known where cytochrome oxidase is located.

Question 18

The yield of ATP from the complete oxidation of glucose is lower in muscle and brain from that in kidney, liver, and heart because

Accepted Answer

A)  there are fewer mitochondria in muscle and brain cells 
B)  muscle and brain cells have a lower requirement for ATP 
C)  different shuttle mechanisms operate to transfer electrons from the cytosol to the mitochondrion in the two sets of tissues 
D)  none of the above 
A)  there are fewer mitochondria in muscle and brain cells 
B)  muscle and brain cells have a lower requirement for ATP 
C)  different shuttle mechanisms operate to transfer electrons from the cytosol to the mitochondrion in the two sets of tissues 
D)  none of the above

Question 19

Depending on how NADH is shuttled from the cytoplasm into the mitochondria, different molar amounts of ATP will be synthesized as each NADH is oxidized.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following is not true of the process of oxidative phosphorylation?

Accepted Answer

A)  protons flow into the mitochondrial matrix through ion channels in the ATP synthase 
B)  the F0 part of the ATP synthase serves as a proton channel 
C)  the F1 part of the ATP synthase is the site of ATP formation 
D)  iron-sulfur proteins bind to the ATP synthase 
A)  protons flow into the mitochondrial matrix through ion channels in the ATP synthase 
B)  the F0 part of the ATP synthase serves as a proton channel 
C)  the F1 part of the ATP synthase is the site of ATP formation 
D)  iron-sulfur proteins bind to the ATP synthase

Exam 20: Electron Transport and Oxidative Phosphorylation

The final reduced species in the electron transport chain is

Which of the following is true?

A species in the electron transport chain that can participate in a two-electron transfer is

Creatine supplements work best for long distance exercise, rather than for quick spurts of energy.

The only complex which actually uses molecular oxygen is

The Q cycle refers to flow of electrons from

The F1F0 complex is actually a transmembrane complex.

Chemiosmotic coupling involves this process:

The reference reaction for determining reduction potentials (E° = 0) is the reduction of

Which of the following procedures is most unique to the determination of the order of the passage of electrons through the electron transport chain was determined

Oxidative phosphorylation is coupled to electron transport in

What is the net yield of ATP per glucose molecule that passes through all of aerobic respiration (glucose → CO2 + H2O)?

Electron flow in the mitochondria follows this pathway:

Which of the following statements concerning E° for an electron-transfer reaction is false?

Which of the following is not a part of the electron transport chain?

Most of the reactions of electron transport in the mitochondria occur

Which complex contains cytochrome oxidase?

The yield of ATP from the complete oxidation of glucose is lower in muscle and brain from that in kidney, liver, and heart because

Depending on how NADH is shuttled from the cytoplasm into the mitochondria, different molar amounts of ATP will be synthesized as each NADH is oxidized.

Which of the following is not true of the process of oxidative phosphorylation?

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

The Importance of Energy Changes and Electron Transfer in Metabolism

Carbohydrates

Glycolysis

Storage Mechanisms and Control in Carbohydrate Metabolism

The Citric Acid Cycle

Lipid Metabolism

Photosynthesis

The Metabolism of Nitrogen

Integration of Metabolism: Cellular Signaling

Filters

The F₁F₀ complex is actually a transmembrane complex.

What is the net yield of ATP per glucose molecule that passes through all of aerobic respiration (glucose → CO₂ + H₂O)?