Question 1

Identify the correct order of electron transfers in the electron transport chain starting from FADH2.

Accepted Answer

A)  complex I $\rightarrow$ complex II $\rightarrow$ complex III $\rightarrow$ complex IV 
B)  complex II $\rightarrow$ complex III $\rightarrow$cytochrome c $\rightarrow$ complex IV 
C)  complex II $\rightarrow$ coenzyme Q $\rightarrow$complex IV $\rightarrow$ ATP synthase 
D)  complex I $\rightarrow$ coenzyme Q $\rightarrow$ complex III $\rightarrow$ complex IV 
A)  complex I $\rightarrow$ complex II $\rightarrow$ complex III $\rightarrow$ complex IV 
B)  complex II $\rightarrow$ complex III $\rightarrow$cytochrome c $\rightarrow$ complex IV 
C)  complex II $\rightarrow$ coenzyme Q $\rightarrow$complex IV $\rightarrow$ ATP synthase 
D)  complex I $\rightarrow$ coenzyme Q $\rightarrow$ complex III $\rightarrow$ complex IV

Question 2

List the major enzymes and enzyme complexes in the oxidative phosphorylation pathway, which are required to couple FADH2 oxidation with ATP synthesis.

Accepted Answer

Complex II (succinate dehydrog

Question 3

In the mitochondrial electron transport system, the electron from NADH moves from __________ the mitochondria through the protein complexes to the
Mitochondria.

Accepted Answer

A)  outside; outside 
B)  outside; inside 
C)  inside; inside 
D)  inside; outside 
A)  outside; outside 
B)  outside; inside 
C)  inside; inside 
D)  inside; outside

Question 4

What is the effect of oligomycin, an ATP synthase inhibitor, on the mitochondrial oxidative phosphorylation pathway?

Accepted Answer

A)  The mitochondria cannot reduce NADH or make ATP. 
B)  No proton gradient is formed, and no ATP is synthesized. 
C)  Protons leak back into the cytoplasm. 
D)  The proton gradient is formed, but no ATP synthesis can occur. 
A)  The mitochondria cannot reduce NADH or make ATP. 
B)  No proton gradient is formed, and no ATP is synthesized. 
C)  Protons leak back into the cytoplasm. 
D)  The proton gradient is formed, but no ATP synthesis can occur.

Question 5

What best describes the driving force for ATP synthesis in the mitochondria?

Accepted Answer

A)  Electron transport from electron transport system complexes. 
B)  The higher pH inside the mitochondria that results from electron transfer. 
C)  The large drops in $\Delta$G resulting from electron transfer in the ETC. 
D)  The substrate level phosphorylations of the TCA cycle and glycolysis. 
A)  Electron transport from electron transport system complexes. 
B)  The higher pH inside the mitochondria that results from electron transfer. 
C)  The large drops in $\Delta$G resulting from electron transfer in the ETC. 
D)  The substrate level phosphorylations of the TCA cycle and glycolysis.

Question 6

Electrons from a succinate molecule can enter into the ETC and result in enough pumped protons to make how many ATPs?

Accepted Answer

A)  2.0 
B)  1.5 
C)  1.0 
D)  2.5 
A)  2.0 
B)  1.5 
C)  1.0 
D)  2.5

Question 7

What would happen if mitochondria were treated with a proton gradient uncoupler, such as 2,4-dinitrophenol?

Accepted Answer

A)  Electron transfer would stop. 
B)  Complex I would become reduced, and complexes III and IV would become oxidized. 
C)  Protons would be pumped by the mitochondrial electron transport chain, although no ATP would be synthesized. 
D)  Reducing equivalents, in the form of NADH, would no longer be consumed. 
A)  Electron transfer would stop. 
B)  Complex I would become reduced, and complexes III and IV would become oxidized. 
C)  Protons would be pumped by the mitochondrial electron transport chain, although no ATP would be synthesized. 
D)  Reducing equivalents, in the form of NADH, would no longer be consumed.

Question 8

The drug oligomycin inhibits ATP synthase by preventing protons from flowing through the enzyme. Oligomycin must bind to the __________ of ATP synthase.

Accepted Answer

A)  catalytic headpiece 
B)  F1 subunit 
C)  ATP binding site 
D)  F0 subunit of 
A)  catalytic headpiece 
B)  F1 subunit 
C)  ATP binding site 
D)  F0 subunit of

Question 9

How many ATPs are produced from the complete metabolism of one glucose molecule, assuming that all resulting NADH and FADH2 is used by the electron transport chain and oxidative phosphorylation to make ATP?

Accepted Answer

A)  4 
B)  16 
C)  32 
D)  102 
A)  4 
B)  16 
C)  32 
D)  102

Question 10

What are the principle physiological electron donors for the mitochondrial electron transport pathway?

Accepted Answer

A)  FADH2 and NADH 
B)  FADH2, NADH, and NADPH 
C)  NADH only 
D)  UQH2, NADH, and FADH2 
A)  FADH2 and NADH 
B)  FADH2, NADH, and NADPH 
C)  NADH only 
D)  UQH2, NADH, and FADH2

Question 11

What is the driving force for ATP synthesis by the ATP synthase enzyme?

Accepted Answer

A)  The electron transfers through the protein complexes. 
B)  ADP + Pi $\rightarrow$ ATP 
C)  The oxidation of NADH to NAD+. 
D)  The pH gradient across the inner mitochondrial membrane. 
A)  The electron transfers through the protein complexes. 
B)  ADP + Pi $\rightarrow$ ATP 
C)  The oxidation of NADH to NAD+. 
D)  The pH gradient across the inner mitochondrial membrane.

Question 12

ATP synthesis occurs

Accepted Answer

A)  on the outer mitochondrial membrane. 
B)  at the ATP synthase complex after ADP and Pi are transported into the mitochondria. 
C)  as a result of the leakage of H+ back out of the mitochondria. 
D)  from the electron transfer reactions through complex IV. 
A)  on the outer mitochondrial membrane. 
B)  at the ATP synthase complex after ADP and Pi are transported into the mitochondria. 
C)  as a result of the leakage of H+ back out of the mitochondria. 
D)  from the electron transfer reactions through complex IV.

Question 13

The resting state of the three $\beta$ subunits in the ATP synthase enzyme is best described as

Accepted Answer

A)  one O, one L, and one T conformation. 
B)  all in O conformations. 
C)  all in L conformations. 
D)  one L and two O conformations. 
A)  one O, one L, and one T conformation. 
B)  all in O conformations. 
C)  all in L conformations. 
D)  one L and two O conformations.

Question 14

List the conformation types and the changes to the substrates in a single $\beta$subunit on the ATP synthase catalytic head piece during one 360o rotation of the rotor.

Accepted Answer

A @#LAT-DLM& subunit begins in the O or open form,

Question 15

The structure of 2,4-dinitrophenol is shown below. Explain how it functions to uncouple a proton gradient across the mitochondrial membrane.

Accepted Answer

@#IMG-DLM& 2,4-dinitrophenol is nonpolar enough th

Question 16

The energy released during mitochondrial electron transport processes is used to

Accepted Answer

A)  make ATP. 
B)  pump protons across the membrane. 
C)  heat the mitochondria. 
D)  synthesize carbohydrates. 
A)  make ATP. 
B)  pump protons across the membrane. 
C)  heat the mitochondria. 
D)  synthesize carbohydrates.

Question 17

What is the cellular location of eukaryotic thermogenin (or uncoupling protein)?

Accepted Answer

A)  mitochondrial inner membrane 
B)  mitochondrial matrix 
C)  cytoplasm 
D)  both cytoplasm and mitochondrial matrix 
A)  mitochondrial inner membrane 
B)  mitochondrial matrix 
C)  cytoplasm 
D)  both cytoplasm and mitochondrial matrix

Question 18

Which of the following is an electron carrier in the mitochondrial electron transport system?

Accepted Answer

A)  proton 
B)  water 
C)  quinone 
D)  ATP 
A)  proton 
B)  water 
C)  quinone 
D)  ATP

Question 19

What enzyme uses the proton motive force for its driving force?

Accepted Answer

A)  complex IV 
B)  ATP synthase 
C)  complex III 
D)  complex I 
A)  complex IV 
B)  ATP synthase 
C)  complex III 
D)  complex I

Question 20

In yeast, it is estimated that approximately H+ are required by ATP synthase per ATP synthesized.

Accepted Answer

A)  1 
B)  3 
C)  9 
D)  10 
A)  1 
B)  3 
C)  9 
D)  10

Exam 11: Oxidative Phosphorylation

Identify the correct order of electron transfers in the electron transport chain starting from FADH2.

List the major enzymes and enzyme complexes in the oxidative phosphorylation pathway, which are required to couple FADH2 oxidation with ATP synthesis.

In the mitochondrial electron transport system, the electron from NADH moves from __________ the mitochondria through the protein complexes to the Mitochondria.

What is the effect of oligomycin, an ATP synthase inhibitor, on the mitochondrial oxidative phosphorylation pathway?

What best describes the driving force for ATP synthesis in the mitochondria?

Electrons from a succinate molecule can enter into the ETC and result in enough pumped protons to make how many ATPs?

What would happen if mitochondria were treated with a proton gradient uncoupler, such as 2,4-dinitrophenol?

The drug oligomycin inhibits ATP synthase by preventing protons from flowing through the enzyme. Oligomycin must bind to the __________ of ATP synthase.

How many ATPs are produced from the complete metabolism of one glucose molecule, assuming that all resulting NADH and FADH2 is used by the electron transport chain and oxidative phosphorylation to make ATP?

What are the principle physiological electron donors for the mitochondrial electron transport pathway?

What is the driving force for ATP synthesis by the ATP synthase enzyme?

ATP synthesis occurs

The resting state of the three β\betaβ subunits in the ATP synthase enzyme is best described as

List the conformation types and the changes to the substrates in a single β\betaβ subunit on the ATP synthase catalytic head piece during one 360o rotation of the rotor.

The structure of 2,4-dinitrophenol is shown below. Explain how it functions to uncouple a proton gradient across the mitochondrial membrane.

The energy released during mitochondrial electron transport processes is used to

What is the cellular location of eukaryotic thermogenin (or uncoupling protein)?

Which of the following is an electron carrier in the mitochondrial electron transport system?

What enzyme uses the proton motive force for its driving force?

In yeast, it is estimated that approximately H+ are required by ATP synthase per ATP synthesized.

Principles of Biochemistry

Physical Biochemistry: Energy Conversion, Water, and Membranes

Nucleic Acid Structure and Function

Protein Structure

Methods in Protein Biochemistry

Protein Function

Enzyme Mechanisms

Cell Signaling Systems

Glycolysis: a Paradigm of Metabolic Regulation

The Citrate Cycle

Photosynthesis

Carbohydrate Structure and Function

Carbohydrate Metabolism

Lipid Structure and Function

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Metabolic Integration

DNA Replication, Repair, and Recombination

RNA Synthesis, Processing, and Gene Silencing

Protein Synthesis, Posttranslational Modification, and Transport

Gene Regulation

Filters

Identify the correct order of electron transfers in the electron transport chain starting from FADH₂.

List the major enzymes and enzyme complexes in the oxidative phosphorylation pathway, which are required to couple FADH₂ oxidation with ATP synthesis.

How many ATPs are produced from the complete metabolism of one glucose molecule, assuming that all resulting NADH and FADH₂ is used by the electron transport chain and oxidative phosphorylation to make ATP?

The resting state of the three $\beta$ subunits in the ATP synthase enzyme is best described as

List the conformation types and the changes to the substrates in a single $\beta$ subunit on the ATP synthase catalytic head piece during one 360^orotation of the rotor.

In yeast, it is estimated that approximately H⁺are required by ATP synthase per ATP synthesized.