Question 1

The protonmotive force is the free energy due to the proton gradient across the inner mitochondrial membrane.

Accepted Answer

A) True 
 B)False

Question 2

Heat can be generated in the brown adipose tissue of hibernating mammals due to .

Accepted Answer

A)  increased ATP production by ATP synthase 
B)  uncoupling by thermogenin 
C)  a greater pH gradient across the inner mitochondrial membrane by complex IV 
D)  insufficient NADH production during the citric acid cycle due to less active pyruvate translocase. 
A)  increased ATP production by ATP synthase 
B)  uncoupling by thermogenin 
C)  a greater pH gradient across the inner mitochondrial membrane by complex IV 
D)  insufficient NADH production during the citric acid cycle due to less active pyruvate translocase.

Question 3

The synthesis of one molecule of ATP from ADP requires to be translocated across the inner mitochondrial membrane.

Accepted Answer

A)  one proton 
B)  three protons 
C)  hundreds of protons 
D)  1 mole of protons 
A)  one proton 
B)  three protons 
C)  hundreds of protons 
D)  1 mole of protons

Question 4

The inner mitochondrial membrane is permeable to water but the outer membrane is not.

Accepted Answer

A) True 
 B)False

Question 5

Which statement is false about complex IV?

Accepted Answer

A)  A binuclear center that contains an iron ion and heme-a3 is the site of the reduction of molecular oxygen to water. 
B)  Bacterial and eukaryotic forms of complex IV have very similar structures and number of subunits per functional unit. 
C)  The core structure of the cytochrome c oxidase in complex IV has three conserved subunits. 
D)  Copper ions shift from a +2 oxidation state to a +1 oxidation state as electrons are passed through the complex. 
A)  A binuclear center that contains an iron ion and heme-a3 is the site of the reduction of molecular oxygen to water. 
B)  Bacterial and eukaryotic forms of complex IV have very similar structures and number of subunits per functional unit. 
C)  The core structure of the cytochrome c oxidase in complex IV has three conserved subunits. 
D)  Copper ions shift from a +2 oxidation state to a +1 oxidation state as electrons are passed through the complex.

Question 6

Mitochondria are about the size of an E. coli cell.

Accepted Answer

A) True 
 B)False

Question 7

Bacteria with superoxide dismutase SOD) can usually grow anaerobically.

Accepted Answer

A) True 
 B)False

Question 8

The number of mitochondria per cell is relatively constant among cell types and species.

Accepted Answer

A) True 
 B)False

Question 9

The inner mitochondrial membrane contributes to the formation of a proton gradient mainly because it

Accepted Answer

A)  contains ATP synthase complex. 
B)  is the location of specific transporter proteins. 
C)  is a barrier to protons. 
D)  is not rich in proteins. 
E)  is rich in proteins. 
A)  contains ATP synthase complex. 
B)  is the location of specific transporter proteins. 
C)  is a barrier to protons. 
D)  is not rich in proteins. 
E)  is rich in proteins.

Question 10

How many protons are translocated across the inner mitochondrial membrane by complex IV for every pair of electrons passing through the electron transport chain?

Accepted Answer

A)  0 
B)  1 
C)  2 
D)  3 
E)  4 
A)  0 
B)  1 
C)  2 
D)  3 
E)  4

Question 11

Most of the free energy needed to drive ATP formation in the mitochondria is the result of an electrical contribution from a charge gradient across the inner mitochondrial membrane.

Accepted Answer

A) True 
 B)False

Question 12

Superoxide dismutase protects cells from damage caused by .

Accepted Answer

A)  ·O2-  
B)  O32-  
C)  H2O2  
D)  H3O+ 
A)  ·O2-  
B)  O32-  
C)  H2O2  
D)  H3O+

Question 13

Complex II in the electron transport chain supplies electrons as to the rest of the chain complexes III and IV).

Accepted Answer

A)  FADH2  
B)  Fe-S 
C)  succinate 
D)  QH2 
A)  FADH2  
B)  Fe-S 
C)  succinate 
D)  QH2

Question 14

Iron sulfur clusters Fs-S) that can accept or donate one electron are found in which complexes of the electron transport chain?

Accepted Answer

A)  I 
B)  II and III 
C)  I, II and III 
D)  I, II, III and IV 
A)  I 
B)  II and III 
C)  I, II and III 
D)  I, II, III and IV

Question 15

What is the Gibbs free energy change, △G, across a membrane with a pH difference of 0.50 and a membrane potential of -0.10 V at 310 K? R = 8.315 J K-1 mol-1; F = 96,485 J V-1 mol-1)

Accepted Answer

A)  -6.85 kJ mol-1  
B)  -12.6 kJ mol-1 
C)  38.6 kJ mol-1  
D)  57.9 kJ mol-1 
A)  -6.85 kJ mol-1  
B)  -12.6 kJ mol-1 
C)  38.6 kJ mol-1  
D)  57.9 kJ mol-1

Question 16

The enzyme complexes associated with oxidative phosphorylation and the electron transport chain can be classified as proteins.

Accepted Answer

A)  integral membrane 
B)  peripheral membrane 
C)  lipid-anchored membrane 
D)  water-soluble 
E)  Both A and C 
A)  integral membrane 
B)  peripheral membrane 
C)  lipid-anchored membrane 
D)  water-soluble 
E)  Both A and C

Question 17

If an inhibitor disrupts the flow of protons from the matrix into the intermembrane space of mitochondria, no ATP will be formed.

Accepted Answer

A) True 
 B)False

Question 18

To reduce one molecule of O2, electrons) must be passed through the electron transport chain and molecules) of NADH isare) oxidized.

Accepted Answer

A)  4; 2 
B)  2; 1 
C)  1; 1 
D)  1; 2 
E)  4; 4 
A)  4; 2 
B)  2; 1 
C)  1; 1 
D)  1; 2 
E)  4; 4

Question 19

Menaquinone has greater reduction potential than FAD.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following substances can freely pass through the inner mitochondrial matrix?

Accepted Answer

A)  H+  
B)  acetate 
C)  CO2  
D)  ATP 
A)  H+  
B)  acetate 
C)  CO2  
D)  ATP

Exam 14: Electron Transport and Oxidative Phosphorylation

The protonmotive force is the free energy due to the proton gradient across the inner mitochondrial membrane.

Heat can be generated in the brown adipose tissue of hibernating mammals due to .

The synthesis of one molecule of ATP from ADP requires to be translocated across the inner mitochondrial membrane.

The inner mitochondrial membrane is permeable to water but the outer membrane is not.

Which statement is false about complex IV?

Mitochondria are about the size of an E. coli cell.

Bacteria with superoxide dismutase SOD) can usually grow anaerobically.

The number of mitochondria per cell is relatively constant among cell types and species.

The inner mitochondrial membrane contributes to the formation of a proton gradient mainly because it

How many protons are translocated across the inner mitochondrial membrane by complex IV for every pair of electrons passing through the electron transport chain?

Most of the free energy needed to drive ATP formation in the mitochondria is the result of an electrical contribution from a charge gradient across the inner mitochondrial membrane.

Superoxide dismutase protects cells from damage caused by .

Complex II in the electron transport chain supplies electrons as to the rest of the chain complexes III and IV).

Iron sulfur clusters Fs-S) that can accept or donate one electron are found in which complexes of the electron transport chain?

What is the Gibbs free energy change, △G, across a membrane with a pH difference of 0.50 and a membrane potential of -0.10 V at 310 K? R = 8.315 J K-1 mol-1; F = 96,485 J V-1 mol-1)

The enzyme complexes associated with oxidative phosphorylation and the electron transport chain can be classified as proteins.

If an inhibitor disrupts the flow of protons from the matrix into the intermembrane space of mitochondria, no ATP will be formed.

To reduce one molecule of O2, electrons) must be passed through the electron transport chain and molecules) of NADH isare) oxidized.

Menaquinone has greater reduction potential than FAD.

Which of the following substances can freely pass through the inner mitochondrial matrix?

Introduction to Biochemistry

Water

Amino Acids and the Primary Structures of Proteins

Proteins: Three-Dimensional Structure and Function

Properties of Enzymes

Mechanisms of Enzymes

Coenzymes and Vitamins

Carbohydrates

Lipids and Membranes

Introduction to Metabolism

Glycolysis

Gluconeogenesis, the Pentose Phosphate Pathway, and Glycogen Metabolism

The Citric Acid Cycle

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Nucleic Acids

Dna Replication, Repair, and Recombination

Transcription and Rna Processing

Protein Synthesis

Recombinant Dna Technology

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What is the Gibbs free energy change, △G, across a membrane with a pH difference of 0.50 and a membrane potential of -0.10 V at 310 K? R = 8.315 J K^-¹mol^-¹; F = 96,485 J V^-¹mol^-¹)

To reduce one molecule of O₂, electrons) must be passed through the electron transport chain and molecules) of NADH isare) oxidized.