Question 1

In the Q cycle coenzyme Q takes part

Accepted Answer

A)  in the oxidized and reduced forms only. 
B)  in the oxidized, reduced, and semiquinone forms. 
C)  in the oxidized and semiquinone forms only. 
D)  in the reduced and semiquinone forms only. 
A)  in the oxidized and reduced forms only. 
B)  in the oxidized, reduced, and semiquinone forms. 
C)  in the oxidized and semiquinone forms only. 
D)  in the reduced and semiquinone forms only.

Question 2

Reduction potentials (E°) are measured by reading a voltmeter,which measures the electron flow between two reaction chambers.

Accepted Answer

A) True 
 B)False

Question 3

Which of the following was not evidence that supported Mitchell's chemiosmotic coupling hypothesis?

Accepted Answer

A)  Closed vessicles were required. Phosphorylation did not occur in a completely soluble environment. 
B)  Vessicles could be prepared from mitochondria and the assymetric location of electron transport protein could be shown. 
C)  The existence of the pH gradient could be demonstrated 
D)  The transfer of electrons from complex I to oxygen was shown 
E)  none of these 
A)  Closed vessicles were required. Phosphorylation did not occur in a completely soluble environment. 
B)  Vessicles could be prepared from mitochondria and the assymetric location of electron transport protein could be shown. 
C)  The existence of the pH gradient could be demonstrated 
D)  The transfer of electrons from complex I to oxygen was shown 
E)  none of these

Question 4

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 5

Brown adipose tissue is partially responsible for generating heat in the young human body.

Accepted Answer

A) True 
 B)False

Question 6

Complex I of the electron transport chain oxidizes ____,reduces ____,and ____ protons in the process.

Accepted Answer

A)  FADH2; coenzyme Q; doesn't pump 
B)  FADH2; coenzyme Q; pumps 
C)  NADH; coenzyme Q; doesn't pump 
D)  NADH; coenzyme Q; pumps 
A)  FADH2; coenzyme Q; doesn't pump 
B)  FADH2; coenzyme Q; pumps 
C)  NADH; coenzyme Q; doesn't pump 
D)  NADH; coenzyme Q; pumps

Question 7

Electron flow in the mitochondria follows this pathway:

Accepted Answer

A)  NADH FMN Coenzyme Q Cyt A Cyt B Cyt C O2 
B)  NADH FMN Cyt B Coenzyme Q Cyt C Cyt A O2 
C)  FMNH2 NAD Coenzyme Q Cyt B Cyt C Cyt A O2 
D)  NADH FMN Coenzyme Q Cyt B Cyt C Cyt A O2 
E)  NADH FMN Cyt B Cyt C Coenzyme Q Cyt A O2 
A)  NADH FMN Coenzyme Q Cyt A Cyt B Cyt C O2 
B)  NADH FMN Cyt B Coenzyme Q Cyt C Cyt A O2 
C)  FMNH2 NAD Coenzyme Q Cyt B Cyt C Cyt A O2 
D)  NADH FMN Coenzyme Q Cyt B Cyt C Cyt A O2 
E)  NADH FMN Cyt B Cyt C Coenzyme Q Cyt A O2

Question 8

Chemiosmotic coupling was first proposed by Peter Mitchell,who won a Nobel Prize for his theory.

Accepted Answer

A) True 
 B)False

Question 9

Another name for Complex II in the electron transport chain is

Accepted Answer

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

Question 10

The P/O ratio refers to the number of moles of ATP produced for each mole of

Accepted Answer

A)  oxygen atoms consumed in electron transport 
B)  oxygen molecules consumed in electron transport 
C)  NADH reoxidized in electron transport 
D)  FADH2 reoxidized in electron transport 
A)  oxygen atoms consumed in electron transport 
B)  oxygen molecules consumed in electron transport 
C)  NADH reoxidized in electron transport 
D)  FADH2 reoxidized in electron transport

Question 11

Which of the following is an advantage of using multiple steps in electron transport?

Accepted Answer

A)  By using several steps the net -DG is higher (more energy is released). 
B)  More heat can be generated by using small steps. 
C)  More energy can be captured to synthesize ATP by using small steps. 
D)  Small steps allow for both more heat generation and more ATP synthesis. 
E)  All of these statements are advantages of using multiple steps. 
A)  By using several steps the net -DG is higher (more energy is released). 
B)  More heat can be generated by using small steps. 
C)  More energy can be captured to synthesize ATP by using small steps. 
D)  Small steps allow for both more heat generation and more ATP synthesis. 
E)  All of these statements are advantages of using multiple steps.

Question 12

Which of the following respiratory inhibitors does not block the final step of electron transport,the reduction of oxygen to form water?

Accepted Answer

A)  Azide (N3+) 
B)  Cyanide (CN1-) 
C)  Carbon Monoxide (CO) 
D)  Rotenone 
E)  All of these block the last reaction of electron transport. 
A)  Azide (N3+) 
B)  Cyanide (CN1-) 
C)  Carbon Monoxide (CO) 
D)  Rotenone 
E)  All of these block the last reaction of electron transport.

Question 13

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

Question 14

A poison that prevents the transfer of electrons from the last iron-sulfur cluster of Complex I to coenzyme Q is added to a suspension of actively respiring mitochondria.Which statement best describes the effect seen?

Accepted Answer

A)  ATP production would be impaired as this would uncouple oxidative phosphorylation from electron transport. 
B)  ATP production would be reduced as fewer protons would be pumped out of the mitochondrial matrix. 
C)  ATP production would be severely impaired as this would completely block electron transport through the electron transport chain. 
D)  This compound would have little to no effect on ATP production. 
A)  ATP production would be impaired as this would uncouple oxidative phosphorylation from electron transport. 
B)  ATP production would be reduced as fewer protons would be pumped out of the mitochondrial matrix. 
C)  ATP production would be severely impaired as this would completely block electron transport through the electron transport chain. 
D)  This compound would have little to no effect on ATP production.

Question 15

Conformation changes in proteins are crucial in the synthesis of ATP in the mitochondria.

Accepted Answer

A) True 
 B)False

Question 16

The ultimate electron acceptor in the electron transport chain is

Accepted Answer

A)  NAD+. 
B)  FAD. 
C)  oxygen. 
D)  ADP. 
A)  NAD+. 
B)  FAD. 
C)  oxygen. 
D)  ADP.

Question 17

Which of the following complexes does not directly contribute to the production of ATP by pumping protons?

Accepted Answer

A)  Complex I. 
B)  Complex II. 
C)  Complex III. 
D)  Complex IV. 
E)  All four complexes pump protons. 
A)  Complex I. 
B)  Complex II. 
C)  Complex III. 
D)  Complex IV. 
E)  All four complexes pump protons.

Question 18

Which of the following terms describes ATP synthesis in mitochondria?

Accepted Answer

A)  substrate-level phosphorylation 
B)  oxidative phosphorylation 
C)  photophosphorylation 
A)  substrate-level phosphorylation 
B)  oxidative phosphorylation 
C)  photophosphorylation

Question 19

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 20

Coenzyme Q can act as an intermediate electron carrier,since the ketone group of the quinone structure is readily reduced to an alcohol.

Accepted Answer

A) True 
 B)False

Exam 20: Electron Transport and Oxidative Phosphorylation

In the Q cycle coenzyme Q takes part

Reduction potentials (E°) are measured by reading a voltmeter,which measures the electron flow between two reaction chambers.

Which of the following was not evidence that supported Mitchell's chemiosmotic coupling hypothesis?

Chemiosmotic coupling involves this process:

Brown adipose tissue is partially responsible for generating heat in the young human body.

Complex I of the electron transport chain oxidizes ____,reduces ____,and ____ protons in the process.

Electron flow in the mitochondria follows this pathway:

Chemiosmotic coupling was first proposed by Peter Mitchell,who won a Nobel Prize for his theory.

Another name for Complex II in the electron transport chain is

The P/O ratio refers to the number of moles of ATP produced for each mole of

Which of the following is an advantage of using multiple steps in electron transport?

Which of the following respiratory inhibitors does not block the final step of electron transport,the reduction of oxygen to form water?

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

A poison that prevents the transfer of electrons from the last iron-sulfur cluster of Complex I to coenzyme Q is added to a suspension of actively respiring mitochondria.Which statement best describes the effect seen?

Conformation changes in proteins are crucial in the synthesis of ATP in the mitochondria.

The ultimate electron acceptor in the electron transport chain is

Which of the following complexes does not directly contribute to the production of ATP by pumping protons?

Which of the following terms describes ATP synthesis in mitochondria?

Electron flow in the mitochondria follows this pathway:

Coenzyme Q can act as an intermediate electron carrier,since the ketone group of the quinone structure is readily reduced to an alcohol.

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

Complex I of the electron transport chain oxidizes ,reduces ,and protons in the process.