Question 1

Which of the following is a mobile electron carrier?

Accepted Answer

A) UQ 
B) [FMN] 
C) Complex I 
D) Complex III 
A) UQ 
B) [FMN] 
C) Complex I 
D) Complex III A

Question 2

Which of the following correct regarding redox couples is NOT?

Accepted Answer

A) Standard reduction potentials are measured relative to a standard hydrogen cell (H⁺/H₂). 
B) For cells in which electrons flow toward the sample half-cell,the reduction potential is positive. 
C) A redox couple consists of a substance being oxidized and the substance oxidizing it. 
D) A half-reaction involving the loss of electrons is an oxidation reaction. 
A) Standard reduction potentials are measured relative to a standard hydrogen cell (H⁺/H₂). 
B) For cells in which electrons flow toward the sample half-cell,the reduction potential is positive. 
C) A redox couple consists of a substance being oxidized and the substance oxidizing it. 
D) A half-reaction involving the loss of electrons is an oxidation reaction. C

Question 3

Which of the following is a characteristic of cyt c?

Accepted Answer

A) It accepts electrons from cyt bH. 
B) It is globular with planar heme group near the centre of the protein. 
C) It is water insoluble. 
D) It is zinc coordinated with histidine nitrogen and methionine sulphur atoms. 
A) It accepts electrons from cyt bH. 
B) It is globular with planar heme group near the centre of the protein. 
C) It is water insoluble. 
D) It is zinc coordinated with histidine nitrogen and methionine sulphur atoms. B

Question 4

Which of the following is a characteristic of the binuclear centre of Complex IV?

Accepted Answer

A) Fe-S is a component. 
B) Water is needed here. 
C) Cyt c is a component. 
D) Two electrons are transferred to bound O₂. 
A) Fe-S is a component. 
B) Water is needed here. 
C) Cyt c is a component. 
D) Two electrons are transferred to bound O₂.

Question 5

Which of the following c-subunit residues of ATP synthase are proton neutralized during ATP synthesis?

Accepted Answer

A) Ser 
B) Asp 
C) Arg 
D) Glu 
A) Ser 
B) Asp 
C) Arg 
D) Glu

Question 6

Which of the following enzymes catalyzes the reaction below?
Dihydroxyacetone phosphate (DHAP)+ NADH →NAD⁺ + glycerol-3-phosphate

Accepted Answer

A) glycerol-3-phosphate dehydrogenase 
B) triose phosphate isomerase 
C) DHAP dehydrogenase 
D) glycerol-3-phosphate reductase 
A) glycerol-3-phosphate dehydrogenase 
B) triose phosphate isomerase 
C) DHAP dehydrogenase 
D) glycerol-3-phosphate reductase

Question 7

Which of the following molecules is the electron donor to Complex III?

Accepted Answer

A) cytochrome c 
B) UQH₂ 
C) NADH 
D) FADH₂ 
A) cytochrome c 
B) UQH₂ 
C) NADH 
D) FADH₂

Question 8

Which of the following components is NOT membrane bound?

Accepted Answer

A) cytochrome ? /? 3 
B) cytochrome c 
C) cytochrome c1 
D) coenzyme Q 
A) cytochrome ? /? 3 
B) cytochrome c 
C) cytochrome c1 
D) coenzyme Q

Question 9

How many electrons are required for the complete reduction of 1 molecule of oxygen gas?

Accepted Answer

A) 2 
B) 3 
C) 4 
D) 6 
A) 2 
B) 3 
C) 4 
D) 6

Question 10

Which of the following resides in the mitochondria?

Accepted Answer

A) enzymes for glycolysis 
B) adenylate cyclase 
C) the pentose phosphate pathway 
D) the electron transport complexes 
A) enzymes for glycolysis 
B) adenylate cyclase 
C) the pentose phosphate pathway 
D) the electron transport complexes

Question 11

Does electron transport stop if rotenone is added? Which of the following explains the reasoning?

Accepted Answer

A) Yes,there is not an electron source. 
B) No,rotenone is not strong enough to inhibit all of the electron-transport chain. 
C) No,there is still a source of electrons from Complex II. 
D) Yes,rotenone inhibits Complex III;therefore,electrons cannot be passed on. 
A) Yes,there is not an electron source. 
B) No,rotenone is not strong enough to inhibit all of the electron-transport chain. 
C) No,there is still a source of electrons from Complex II. 
D) Yes,rotenone inhibits Complex III;therefore,electrons cannot be passed on.

Question 12

Which of the following components is NOT part of cytochrome c oxidase (Complex IV)?

Accepted Answer

A) CuA 
B) CuB 
C) cyt c1 
D) cyt a3 
A) CuA 
B) CuB 
C) cyt c1 
D) cyt a3

Question 13

How many protons are released by Complex III on the intermembrane side for each pair of electrons that pass through the Q cycle?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 14

Which of the following is another term used to define Complex II in the electron-transport chain?

Accepted Answer

A) cytochrome c oxidase 
B) NADH-CoQ reductase 
C) succinate-CoQ reductase 
D) cytochrome bc1 complex 
A) cytochrome c oxidase 
B) NADH-CoQ reductase 
C) succinate-CoQ reductase 
D) cytochrome bc1 complex

Question 15

Which of the following does NOT transfer electrons to the UQ/UQH₂ pool?

Accepted Answer

A) Complex I 
B) fatty acyl-CoA dehydrogenase 
C) Complex IV 
D) sn-glycerophosphate dehydrogenase 
A) Complex I 
B) fatty acyl-CoA dehydrogenase 
C) Complex IV 
D) sn-glycerophosphate dehydrogenase

Question 16

Which of the following is a part of apoptosis?

Accepted Answer

A) deactivation of caspases 
B) mitochondrial membrane permeabilization (MMP) 
C) closure of the mitochondrial outer membrane protein-permeable pores 
D) a series of anabolic reactions 
A) deactivation of caspases 
B) mitochondrial membrane permeabilization (MMP) 
C) closure of the mitochondrial outer membrane protein-permeable pores 
D) a series of anabolic reactions

Question 17

Which of the following enzymes is NOT a flavoprotein?

Accepted Answer

A) NADH-CoQ reductase 
B) succinate dehydrogenase 
C) coenzyme Q-cytochrome c oxidoreductase 
D) fatty acyl-CoA dehydrogenase-transferring protein 
A) NADH-CoQ reductase 
B) succinate dehydrogenase 
C) coenzyme Q-cytochrome c oxidoreductase 
D) fatty acyl-CoA dehydrogenase-transferring protein

Question 18

Which of the following reaction classifications has a standard reduction potential that is positive under standard conditions?

Accepted Answer

A) restrained 
B) structured 
C) planned 
D) spontaneous 
A) restrained 
B) structured 
C) planned 
D) spontaneous

Question 19

Which of the following regarding redox reactions is NOT correct?

Accepted Answer

A) Standard free energy change for a redox reaction is related to the standard reduction potential. 
B) Standard free energy change for a redox reaction is related to the number of electrons transferred. 
C) For redox reactions with negative standard reduction potentials,standard free energy change is negative. 
D) Redox reactions must occur in pairs,where the total number of electrons involved in the oxidation equals the total number involved in the reduction. 
A) Standard free energy change for a redox reaction is related to the standard reduction potential. 
B) Standard free energy change for a redox reaction is related to the number of electrons transferred. 
C) For redox reactions with negative standard reduction potentials,standard free energy change is negative. 
D) Redox reactions must occur in pairs,where the total number of electrons involved in the oxidation equals the total number involved in the reduction.

Question 20

Which of the following metabolic pathways is NOT linked to the electron-transport chain through Complex I,which accepts electrons from NADH?

Accepted Answer

A) gluconeogenesis 
B) glycolysis 
C) TCA cycle 
D) fatty acid oxidation 
A) gluconeogenesis 
B) glycolysis 
C) TCA cycle 
D) fatty acid oxidation

Exam 19: Electron Transport and Oxidative Phosphorylation

Which of the following is a mobile electron carrier?

Which of the following correct regarding redox couples is NOT?

Which of the following is a characteristic of cyt c?

Which of the following is a characteristic of the binuclear centre of Complex IV?

Which of the following c-subunit residues of ATP synthase are proton neutralized during ATP synthesis?

Which of the following enzymes catalyzes the reaction below? Dihydroxyacetone phosphate (DHAP)+ NADH →NAD⁺ + glycerol-3-phosphate

Which of the following molecules is the electron donor to Complex III?

Which of the following components is NOT membrane bound?

How many electrons are required for the complete reduction of 1 molecule of oxygen gas?

Which of the following resides in the mitochondria?

Does electron transport stop if rotenone is added? Which of the following explains the reasoning?

Which of the following components is NOT part of cytochrome c oxidase (Complex IV)?

How many protons are released by Complex III on the intermembrane side for each pair of electrons that pass through the Q cycle?

Which of the following is another term used to define Complex II in the electron-transport chain?

Which of the following does NOT transfer electrons to the UQ/UQH₂ pool?

Which of the following is a part of apoptosis?

Which of the following enzymes is NOT a flavoprotein?

Which of the following reaction classifications has a standard reduction potential that is positive under standard conditions?

Which of the following regarding redox reactions is NOT correct?

Which of the following metabolic pathways is NOT linked to the electron-transport chain through Complex I,which accepts electrons from NADH?

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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