Question 1

Oxidative phosphorylation occurs in the mitochondrial membrane in eukaryotes and the plasma membrane in bacteria.

Accepted Answer

A) True 
 B)False  True

Question 2

Both fumarate reductase and succinate dehydrogenase can function at the same time in E. coli.

Accepted Answer

A) True 
 B)False  False

Question 3

Which has the highest reduction potential?

Accepted Answer

A)  NADH 
B)  complex I 
C)  complex II 
D)  O2 
A)  NADH 
B)  complex I 
C)  complex II 
D)  O2 D

Question 4

Complex I contains a porin protein subunit that transports H+ across the inner mitochondrial membrane.

Accepted Answer

A) True 
 B)False

Question 5

The numbers of mitochondria in cells is closely associated with cell function.

Accepted Answer

A) True 
 B)False

Question 6

In the mitochondria NADH and QH2 are essentially oxidized by since it is the terminal electron acceptor.

Accepted Answer

A)  carbon dioxide 
B)  hydrogen peroxide 
C)  ozone 
D)  oxygen 
A)  carbon dioxide 
B)  hydrogen peroxide 
C)  ozone 
D)  oxygen

Question 7

ATP synthase is located in the of the mitochondrion.

Accepted Answer

A)  outer membrane 
B)  inner membrane 
C)  matrix 
D)  intermembrane space 
A)  outer membrane 
B)  inner membrane 
C)  matrix 
D)  intermembrane space

Question 8

An obligate anaerobe cannot grow in the presence of oxygen.

Accepted Answer

A) True 
 B)False

Question 9

The chemiosmotic theory is a concept that .

Accepted Answer

A)  the transport of Na+ and K+ across cell membranes is by active transport 
B)  explains how transport by facilitated diffusion reaches a saturation limit 
C)  explains the blood-brain barrier 
D)  a proton gradient that drives the formation of ATP 
A)  the transport of Na+ and K+ across cell membranes is by active transport 
B)  explains how transport by facilitated diffusion reaches a saturation limit 
C)  explains the blood-brain barrier 
D)  a proton gradient that drives the formation of ATP

Question 10

If the difference in pH across a membrane is 0.60 and the membrane potential is -0.10 V, about what percent of the Gibbs free energy change, △G, is from the pH difference at 37 oC? R = 8.315 J K-1 mol-1; F = 96,485 J V-1 mol-1)

Accepted Answer

A)  15% 
B)  27% 
C)  73% 
D)  85% 
A)  15% 
B)  27% 
C)  73% 
D)  85%

Question 11

The oxidizing agent in the enzyme superoxide dismutase is

Accepted Answer

A)  superoxide anion ·O2-). 
B)  H2O2. 
C)  Copper. 
D)  O2. 
E)  All of the above 
A)  superoxide anion ·O2-). 
B)  H2O2. 
C)  Copper. 
D)  O2. 
E)  All of the above

Question 12

The P/O ratio for passing electrons through complexes I, III and IV is .

Accepted Answer

A)  1 
B)  1.5 
C)  2 
D)  2.5 
E)  3 
A)  1 
B)  1.5 
C)  2 
D)  2.5 
E)  3

Question 13

A muscle cell from an alligator jaw contains more mitochondria than a wing muscle of a migrating bird such as a goose.

Accepted Answer

A) True 
 B)False

Question 14

The P/O ratio is independent of whether electrons originate from complex I or complex II.

Accepted Answer

A) True 
 B)False

Question 15

What feature of cytochromes makes them valuable in electron transport systems?

Accepted Answer

A)  aspartate residues in the active site 
B)  the porphyrin ring 
C)  the multiple α-helices 
D)  the iron ion 
A)  aspartate residues in the active site 
B)  the porphyrin ring 
C)  the multiple α-helices 
D)  the iron ion

Question 16

Oxidative phosphorylation requires all of the items listed below except

Accepted Answer

A)  ATP synthase in the correct position in the membrane. 
B)  enzyme complexes embedded in a membrane. 
C)  the flow of electrons from NADH and QH2 in the membrane. 
D)  a matrix more positively charged than the intermembrane space. 
E)  a terminal electron acceptor which is H2O in mitochondria. 
A)  ATP synthase in the correct position in the membrane. 
B)  enzyme complexes embedded in a membrane. 
C)  the flow of electrons from NADH and QH2 in the membrane. 
D)  a matrix more positively charged than the intermembrane space. 
E)  a terminal electron acceptor which is H2O in mitochondria.

Question 17

The reduction potential of Complex I is lower than that of Complex III.

Accepted Answer

A) True 
 B)False

Question 18

Electron flow to oxidize electron carriers does not occur in anaerobic organisms.

Accepted Answer

A) True 
 B)False

Question 19

The terminal electron acceptor for complex III of the electron transport chain is .

Accepted Answer

A)  Q 
B)  Fe-S 
C)  FAD 
D)  cytochrome c 
A)  Q 
B)  Fe-S 
C)  FAD 
D)  cytochrome c

Question 20

The oxidation-reduction cofactor in the multisubunit enzyme fumarate reductase in E. coli which has the greatest reduction potential is

Accepted Answer

A)  FAD. 
B)  iron clusters. 
C)  ubiquinone. 
D)  menaquinone. 
E)  NADH. 
A)  FAD. 
B)  iron clusters. 
C)  ubiquinone. 
D)  menaquinone. 
E)  NADH.

Exam 14: Electron Transport and Oxidative Phosphorylation

Oxidative phosphorylation occurs in the mitochondrial membrane in eukaryotes and the plasma membrane in bacteria.

Both fumarate reductase and succinate dehydrogenase can function at the same time in E. coli.

Which has the highest reduction potential?

Complex I contains a porin protein subunit that transports H+ across the inner mitochondrial membrane.

The numbers of mitochondria in cells is closely associated with cell function.

In the mitochondria NADH and QH2 are essentially oxidized by since it is the terminal electron acceptor.

ATP synthase is located in the of the mitochondrion.

An obligate anaerobe cannot grow in the presence of oxygen.

The chemiosmotic theory is a concept that .

If the difference in pH across a membrane is 0.60 and the membrane potential is -0.10 V, about what percent of the Gibbs free energy change, △G, is from the pH difference at 37 oC? R = 8.315 J K-1 mol-1; F = 96,485 J V-1 mol-1)

The oxidizing agent in the enzyme superoxide dismutase is

The P/O ratio for passing electrons through complexes I, III and IV is .

A muscle cell from an alligator jaw contains more mitochondria than a wing muscle of a migrating bird such as a goose.

The P/O ratio is independent of whether electrons originate from complex I or complex II.

What feature of cytochromes makes them valuable in electron transport systems?

Oxidative phosphorylation requires all of the items listed below except

The reduction potential of Complex I is lower than that of Complex III.

Electron flow to oxidize electron carriers does not occur in anaerobic organisms.

The terminal electron acceptor for complex III of the electron transport chain is .

The oxidation-reduction cofactor in the multisubunit enzyme fumarate reductase in E. coli which has the greatest reduction potential is

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

Filters

Complex I contains a porin protein subunit that transports H⁺across the inner mitochondrial membrane.

In the mitochondria NADH and QH₂are essentially oxidized by since it is the terminal electron acceptor.

If the difference in pH across a membrane is 0.60 and the membrane potential is -0.10 V, about what percent of the Gibbs free energy change, △G, is from the pH difference at 37 ^oC? R = 8.315 J K^-¹mol^-¹; F = 96,485 J V^-¹mol^-¹)