Question 1

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 2

Electron transport chains occur only in the inner mitochondrial membrane of animal cells or the plasma membrane of bacteria.

Accepted Answer

A) True 
 B)False

Question 3

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

Accepted Answer

A) True 
 B)False

Question 4

Fumarate reductase essentially catalyzes the reverse reaction catalyzed by the succinate dehydrogenase.

Accepted Answer

A) True 
 B)False

Question 5

The enzyme complexes I-IV in the electron transport chain associate with each other by a combination of hydrophobic interactions,disulfide bridges and hydrogen bonding.

Accepted Answer

A) True 
 B)False

Question 6

Energy from electron transport reactions is stored as a ________ gradient that is higher in the intermembrane space than in the mitochondrial matrix.

Accepted Answer

A) electron 
B) ATP 
C) proton 
D) NADPH 
A) electron 
B) ATP 
C) proton 
D) NADPH

Question 7

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

Accepted Answer

A) True 
 B)False

Question 8

White blood cells in mammals can produce toxic superoxide ions to kill bacterial cells.

Accepted Answer

A) True 
 B)False

Question 9

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 10

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

Accepted Answer

A) True 
 B)False

Question 11

An obligate anaerobe cannot grow in the presence of oxygen.

Accepted Answer

A) True 
 B)False

Question 12

Which of the following is mismatched?

Accepted Answer

A) Outer mitochondrial membrane - permeable to ions and water. 
B) Inner mitochondrial membrane - permeable to O2 and CO2. 
C) Outer mitochondrial membrane - folded into cristae. 
D) Inner mitochondrial membrane - location of ATP synthase. 
E) Matrix - some ATP synthase subunits extend here. 
A) Outer mitochondrial membrane - permeable to ions and water. 
B) Inner mitochondrial membrane - permeable to O2 and CO2. 
C) Outer mitochondrial membrane - folded into cristae. 
D) Inner mitochondrial membrane - location of ATP synthase. 
E) Matrix - some ATP synthase subunits extend here.

Question 13

Overall,the membrane-associated electron transport system pumps ________ protons across the membrane for every molecule of NADH that is oxidized.

Accepted Answer

A) 2 
B) 5 
C) 6 
D) 10 
A) 2 
B) 5 
C) 6 
D) 10

Question 14

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 15

Where is oxygen reduced with respect to Complex IV of the electron transport chain?

Accepted Answer

A) In the matrix itself,but close to a portion of Complex IV that extends into the matrix. 
B) Near the inner membrane space side of the membrane on the surface of Complex IV. 
C) Near the matrix side of the membrane on the surface of Complex IV. 
D) At a site buried in the protein,but connected to the transport of electrons by a line of water molecules. 
E) Freely in the hydrophobic portion of the lipid bilayer. 
A) In the matrix itself,but close to a portion of Complex IV that extends into the matrix. 
B) Near the inner membrane space side of the membrane on the surface of Complex IV. 
C) Near the matrix side of the membrane on the surface of Complex IV. 
D) At a site buried in the protein,but connected to the transport of electrons by a line of water molecules. 
E) Freely in the hydrophobic portion of the lipid bilayer.

Question 16

As electrons flow through complexes in the inner mitochondrial membrane,protons are moved from the matrix to the intermembrane space.This can make the pH

Accepted Answer

A) the same in the matrix and the inner membrane space. 
B) lower in the matrix. 
C) lower in both the matrix and the inner mitochondrial space. 
D) lower in the inner membrane space. 
A) the same in the matrix and the inner membrane space. 
B) lower in the matrix. 
C) lower in both the matrix and the inner mitochondrial space. 
D) lower in the inner membrane space.

Question 17

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.

Question 18

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 19

The chemiosmotic theory explains

Accepted Answer

A) the phosphorylation of ADP. 
B) the electron transport chain. 
C) the differences between inner and outer mitochondrial membranes. 
D) the source of energy for formation of mitochondrial ATP. 
E) aerobic respiration. 
A) the phosphorylation of ADP. 
B) the electron transport chain. 
C) the differences between inner and outer mitochondrial membranes. 
D) the source of energy for formation of mitochondrial ATP. 
E) aerobic respiration.

Question 20

In prokaryotes what is the cellular location of the electron transport chain and ATP synthase complexes?

Accepted Answer

A) Plasma membrane. 
B) Cytosol. 
C) Inner mitochondrial membrane. 
D) Endoplasmic reticulum. 
E) Ribosome. 
A) Plasma membrane. 
B) Cytosol. 
C) Inner mitochondrial membrane. 
D) Endoplasmic reticulum. 
E) Ribosome.

Exam 14: Electron Transport and Atp Synthesis

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

Electron transport chains occur only in the inner mitochondrial membrane of animal cells or the plasma membrane of bacteria.

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

Fumarate reductase essentially catalyzes the reverse reaction catalyzed by the succinate dehydrogenase.

The enzyme complexes I-IV in the electron transport chain associate with each other by a combination of hydrophobic interactions,disulfide bridges and hydrogen bonding.

Energy from electron transport reactions is stored as a ________ gradient that is higher in the intermembrane space than in the mitochondrial matrix.

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

White blood cells in mammals can produce toxic superoxide ions to kill bacterial cells.

ATP synthase is located in the ________ of the mitochondrion.

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

An obligate anaerobe cannot grow in the presence of oxygen.

Which of the following is mismatched?

Overall,the membrane-associated electron transport system pumps ________ protons across the membrane for every molecule of NADH that is oxidized.

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

Where is oxygen reduced with respect to Complex IV of the electron transport chain?

As electrons flow through complexes in the inner mitochondrial membrane,protons are moved from the matrix to the intermembrane space.This can make the pH

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

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 chemiosmotic theory explains

In prokaryotes what is the cellular location of the electron transport chain and ATP synthase complexes?

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

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