Question 1

Which of the following is the common product produced by Complex I and Complex II?

Accepted Answer

A) FAD 
B) reduced coenzyme Q 
C) NAD⁺ 
D) reduced O₂ 
A) FAD 
B) reduced coenzyme Q 
C) NAD⁺ 
D) reduced O₂

Question 2

Which of the following complexes reduces molecular oxygen?

Accepted Answer

A) Complex I 
B) Complex II 
C) Complex III 
D) Complex IV 
A) Complex I 
B) Complex II 
C) Complex III 
D) Complex IV

Question 3

Which of the following does NOT occur in the malate-aspartate shuttle?

Accepted Answer

A) OAA is transaminated to aspartate. 
B) OAA is reduced to malate. 
C) Malate is oxidized to OAA. 
D) Aspartate is translocated to the matrix. 
A) OAA is transaminated to aspartate. 
B) OAA is reduced to malate. 
C) Malate is oxidized to OAA. 
D) Aspartate is translocated to the matrix.

Question 4

Which of the following is the source for the energy that drives ATP synthesis?

Accepted Answer

A) the proton gradient 
B) NAD⁺ and FAD 
C) the electron gradient 
D) molecular oxygen 
A) the proton gradient 
B) NAD⁺ and FAD 
C) the electron gradient 
D) molecular oxygen

Question 5

Which of the following takes place in the Q cycle?

Accepted Answer

A) Two protons are pumped into the matrix. 
B) Electrons are transferred from bH to bL. 
C) Two electrons are passed from bL to UQ. 
D) One UQH₂ is returned to the pool. 
A) Two protons are pumped into the matrix. 
B) Electrons are transferred from bH to bL. 
C) Two electrons are passed from bL to UQ. 
D) One UQH₂ is returned to the pool.

Question 6

Which of the following is the effect of adding oligomycin and then 2,4-dinitrophenol to respiring mitochondria?

Accepted Answer

A) Electron transport speeds up and ATP synthesis stops. 
B) Electron transport continues and ATP synthesis continues. 
C) Electron transport stops and ATP synthesis stops. 
D) Electron transport stops and ATP synthesis continues. 
A) Electron transport speeds up and ATP synthesis stops. 
B) Electron transport continues and ATP synthesis continues. 
C) Electron transport stops and ATP synthesis stops. 
D) Electron transport stops and ATP synthesis continues.

Question 7

Which of the following molecules is least likely to be transported across the inner mitochondrial membrane?

Accepted Answer

A) NADH 
B) citrate 
C) pyruvate 
D) malate 
A) NADH 
B) citrate 
C) pyruvate 
D) malate

Question 8

Which of the following subunits in ATP synthase is anchored to the rotor?

Accepted Answer

A) α 
B) β 
C) γ 
D) c 
A) α 
B) β 
C) γ 
D) c

Question 9

Which of the following components is a 2-electron donor?

Accepted Answer

A) FAD 
B) Fe-S 
C) NADH 
D) cyt c 
A) FAD 
B) Fe-S 
C) NADH 
D) cyt c

Question 10

Which of the following is a characteristic of the F₁ unit of ATP synthase?

Accepted Answer

A) The α- and β-subunits are not homologous 
B) It consists of 6 different kinds of subunits. 
C) It catalyzes ATP synthesis but not ATP hydrolysis. 
D) The β-subunits have catalytic sites for ATP synthesis. 
A) The α- and β-subunits are not homologous 
B) It consists of 6 different kinds of subunits. 
C) It catalyzes ATP synthesis but not ATP hydrolysis. 
D) The β-subunits have catalytic sites for ATP synthesis.

Question 11

Which of the following is a property of uncouplers?

Accepted Answer

A) They enhance the proton gradient. 
B) Electron transport continues. 
C) ATP/ADP ratio increases. 
D) Water is produced. 
A) They enhance the proton gradient. 
B) Electron transport continues. 
C) ATP/ADP ratio increases. 
D) Water is produced.

Question 12

Which of the following is the final electron acceptor in the electron-transport chain?

Accepted Answer

A) molecular oxygen 
B) H₂O 
C) cytochrome c 
D) NAD⁺ 
A) molecular oxygen 
B) H₂O 
C) cytochrome c 
D) NAD⁺

Question 13

Which of the following explains why bacteria and other prokaryotic cells have the capacity to get more ATP/glucose oxidized than eukaryotic cells?

Accepted Answer

A) They are simpler and have less going on. 
B) They do not have to use shuttles to reoxidize reduced nucleotides. 
C) They do not have to translocate ATP-ADP across the mitochondrial membranes. 
D) They use an electron-transport chain that translocates more protons. 
A) They are simpler and have less going on. 
B) They do not have to use shuttles to reoxidize reduced nucleotides. 
C) They do not have to translocate ATP-ADP across the mitochondrial membranes. 
D) They use an electron-transport chain that translocates more protons.

Question 14

NADH is a strong reducing agent.What kind of reduction potential does it possess?

Accepted Answer

A) large positive value 
B) large negative value 
C) small positive value 
D) small negative value 
A) large positive value 
B) large negative value 
C) small positive value 
D) small negative value

Question 15

Which of the following is a property of coenzyme Q?

Accepted Answer

A) It is hydrophilic. 
B) It cannot diffuse easily in the membrane. 
C) It has 3 oxidation states. 
D) It shuttles from Complex I and Complex II to Complex IV. 
A) It is hydrophilic. 
B) It cannot diffuse easily in the membrane. 
C) It has 3 oxidation states. 
D) It shuttles from Complex I and Complex II to Complex IV.

Question 16

Which of the following is need for the spontaneity of a redox reaction?

Accepted Answer

A) electron flow 
B) concentration of the species being oxidized 
C) concentration of the species being reduced 
D) standard reduction potential 
A) electron flow 
B) concentration of the species being oxidized 
C) concentration of the species being reduced 
D) standard reduction potential

Question 17

Which of the following is a characteristic of the binding charge mechanism?

Accepted Answer

A) Energy-driven conformational changes convert O-sites to L-sites. 
B) One site is empty (L-sites). 
C) One site contains ADP and Pi (O-sites). 
D) T-sites become O-sites. 
A) Energy-driven conformational changes convert O-sites to L-sites. 
B) One site is empty (L-sites). 
C) One site contains ADP and Pi (O-sites). 
D) T-sites become O-sites.

Question 18

Which of the following is NOT a property of the mitochondrial glycerol-3-phosphate dehydrogenases?

Accepted Answer

A) The mitochondrial enzyme family has bound coenzyme Q. 
B) They work to carry electrons into mitochondria. 
C) One is located in the inner mitochondrial membrane. 
D) There exists an FAD-dependent mitochondrial enzyme. 
A) The mitochondrial enzyme family has bound coenzyme Q. 
B) They work to carry electrons into mitochondria. 
C) One is located in the inner mitochondrial membrane. 
D) There exists an FAD-dependent mitochondrial enzyme.

Question 19

Which of the following is NOT a characteristic of proton gradient-driven enzyme conformational change in ATP synthase?

Accepted Answer

A) binding of substrates 
B) catalytic cooperativity between subunits 
C) conformational change in the β-subunits releasing ATP 
D) rotation of (αβ)3 complex relative to a fixed β-subunit 
A) binding of substrates 
B) catalytic cooperativity between subunits 
C) conformational change in the β-subunits releasing ATP 
D) rotation of (αβ)3 complex relative to a fixed β-subunit

Question 20

Which of the following components part of Complex I?

Accepted Answer

A) [FAD] 
B) cytochrome c 
C) Fe-2S clusters 
D) 4Fe-4S clusters 
A) [FAD] 
B) cytochrome c 
C) Fe-2S clusters 
D) 4Fe-4S clusters

Exam 19: Electron Transport and Oxidative Phosphorylation

Which of the following is the common product produced by Complex I and Complex II?

Which of the following complexes reduces molecular oxygen?

Which of the following does NOT occur in the malate-aspartate shuttle?

Which of the following is the source for the energy that drives ATP synthesis?

Which of the following takes place in the Q cycle?

Which of the following is the effect of adding oligomycin and then 2,4-dinitrophenol to respiring mitochondria?

Which of the following molecules is least likely to be transported across the inner mitochondrial membrane?

Which of the following subunits in ATP synthase is anchored to the rotor?

Which of the following components is a 2-electron donor?

Which of the following is a characteristic of the F₁ unit of ATP synthase?

Which of the following is a property of uncouplers?

Which of the following is the final electron acceptor in the electron-transport chain?

Which of the following explains why bacteria and other prokaryotic cells have the capacity to get more ATP/glucose oxidized than eukaryotic cells?

NADH is a strong reducing agent.What kind of reduction potential does it possess?

Which of the following is a property of coenzyme Q?

Which of the following is need for the spontaneity of a redox reaction?

Which of the following is a characteristic of the binding charge mechanism?

Which of the following is NOT a property of the mitochondrial glycerol-3-phosphate dehydrogenases?

Which of the following is NOT a characteristic of proton gradient-driven enzyme conformational change in ATP synthase?

Which of the following components part of Complex I?

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

Water: the Medium of Life

Thermodynamics of Biological Systems

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

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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