Question 1

The first half of the Q cycle results in which of the following?

Accepted Answer

A)  transfer of 4 protons to the intermembrane space 
B)  a semiquinone radical (UQ∙-) in the Qn site 
C)  2 molecules of reduced cytochrome c​ 
D)  return of one UQH2 to the coenzyme Q pool 
E)  none of the above 
A)  transfer of 4 protons to the intermembrane space 
B)  a semiquinone radical (UQ∙-) in the Qn site 
C)  2 molecules of reduced cytochrome c​ 
D)  return of one UQH2 to the coenzyme Q pool 
E)  none of the above

Question 2

Discuss Peter Mitchell's chemiosmotic hypothesis.​

Accepted Answer

In this hypothesis, protons are driven a

Question 3

All are properties of glycerol-3-phosphate dehydrogenases EXCEPT:

Accepted Answer

A)  one is located in the cytosol. 
B)  works to carry electrons into mitochondria. 
C)  one is located in the inner mitochondrial membrane. 
D)  mitochondrial enzyme has bound coenzyme Q. 
E)  FAD-dependent mitochondrial enzyme. 
A)  one is located in the cytosol. 
B)  works to carry electrons into mitochondria. 
C)  one is located in the inner mitochondrial membrane. 
D)  mitochondrial enzyme has bound coenzyme Q. 
E)  FAD-dependent mitochondrial enzyme.

Question 4

The malate-aspartate shuttle transfers ____ from cytosol to matrix while _____ moves from matrix to cytosol

Accepted Answer

A)  malate; glutamate 
B)  α-ketoglutarate; aspartate 
C)  malate; α-ketoglutarate 
D)  aspartate; malate 
E)  glutamate; malate 
A)  malate; glutamate 
B)  α-ketoglutarate; aspartate 
C)  malate; α-ketoglutarate 
D)  aspartate; malate 
E)  glutamate; malate

Question 5

Which of the following is a two-electron donor?

Accepted Answer

A)  FAD 
B)  Fe−S 
C)  NADH 
D)  NAD+ 
E)  cyt c 
A)  FAD 
B)  Fe−S 
C)  NADH 
D)  NAD+ 
E)  cyt c

Question 6

Bacteria and other prokaryotic cells have the capacity to get more ATP/glucose oxidized than eukaryotic cells because ____, so they are more efficient.

Accepted Answer

A)  they are simpler and have less going on 
B)  they don't have to use shuttles to reoxidize reduced nucleotides 
C)  they do not have to translocate ATP-ADP across the mitochondrial membranes 
D)  they use an electron transport chain that translocates more protons 
E)  none of the above 
A)  they are simpler and have less going on 
B)  they don't have to use shuttles to reoxidize reduced nucleotides 
C)  they do not have to translocate ATP-ADP across the mitochondrial membranes 
D)  they use an electron transport chain that translocates more protons 
E)  none of the above

Question 7

Reduction involves the ____ of electron(s), and reactions for which the standard cell potential is ____ are spontaneous under standard conditions.

Accepted Answer

A)  loss; negative 
B)  loss; positive 
C)  gain; negative 
D)  gain; positive 
E)  none of the above 
A)  loss; negative 
B)  loss; positive 
C)  gain; negative 
D)  gain; positive 
E)  none of the above

Question 8

Which complex reduces molecular oxygen?

Accepted Answer

A)  complex I 
B)  complex II 
C)  complex III 
D)  UQH/UQH2 pool 
E)  complex IV 
A)  complex I 
B)  complex II 
C)  complex III 
D)  UQH/UQH2 pool 
E)  complex IV

Question 9

Which of the following complex(es) translocate protons in the inner mitochondrial membrane?

Accepted Answer

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

Question 10

ATP made in glycolysis and the TCA cycle is the result of ____ phosphorylation, and NADH-dependent ATP synthesis is the result of ____ phosphorylation.

Accepted Answer

A)  oxidative; substrate-level 
B)  oxidative; electron 
C)  substrate-level; electron 
D)  substrate-level; oxidative 
E)  proton-gradient; oxidative 
A)  oxidative; substrate-level 
B)  oxidative; electron 
C)  substrate-level; electron 
D)  substrate-level; oxidative 
E)  proton-gradient; oxidative

Question 11

All are linked to the electron-transport chain through Complex I accepting electrons from NADH EXCEPT:

Accepted Answer

A)  gluconeogenesis. 
B)  glycolysis. 
C)  TCA cycle. 
D)  fatty acid oxidation. 
E)  all are true. 
A)  gluconeogenesis. 
B)  glycolysis. 
C)  TCA cycle. 
D)  fatty acid oxidation. 
E)  all are true.

Question 12

Which of the following is an inhibitor of Complex IV?

Accepted Answer

A)  rotenone 
B)  oligomycin 
C)  antimycin 
D)  cyanide 
E)  all of the above 
A)  rotenone 
B)  oligomycin 
C)  antimycin 
D)  cyanide 
E)  all of the above

Question 13

Does electron transport stop if rotenone is added? Why?

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 can not be passed on. 
E)  Can not be determined from the information given. 
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 can not be passed on. 
E)  Can not be determined from the information given.

Question 14

All are single-electron carriers EXCEPT:

Accepted Answer

A)  UQH2. 
B)  Cyt bL. 
C)  Cyt bH. 
D)  Rieske protein Fe−S clusters. 
E)  Cyt c1. 
A)  UQH2. 
B)  Cyt bL. 
C)  Cyt bH. 
D)  Rieske protein Fe−S clusters. 
E)  Cyt c1.

Question 15

All of the following are properties of ATP synthase EXCEPT:

Accepted Answer

A)  the F1 subunit is attached to the integral membrane protein F0. 
B)  the F0 subunit is hydrophilic. 
C)  transmembrane channel for protons. 
D)  beta-subunits have the catalytic site for ATP synthesis. 
E)  the ring of c subunits form a rotor with respect to the alpha subunits. 
A)  the F1 subunit is attached to the integral membrane protein F0. 
B)  the F0 subunit is hydrophilic. 
C)  transmembrane channel for protons. 
D)  beta-subunits have the catalytic site for ATP synthesis. 
E)  the ring of c subunits form a rotor with respect to the alpha subunits.

Question 16

If an ATP synthase contains 10 c subunits, 3 α subunits and 3 β subunits, how many protons must pass through this complex for every ATP molecule synthesized (assuming that all of the protons are used for ATP synthesis)?

Accepted Answer

A)  0.3 
B)  3 
C)  3.3 
D)  10 
E)  cannot be determined 
A)  0.3 
B)  3 
C)  3.3 
D)  10 
E)  cannot be determined

Question 17

All are correct about the glycerophosphate shuttle EXCEPT:

Accepted Answer

A)  there are two distinct forms of glycerol-3-phosphate dehydrogenase in cells with this shuttle. 
B)  it results in the net transfer of electrons to the electron transport chain from NADH in the cytosol. 
C)  glycerol-3-phosphate is translocated across the inner mitochondrial membrane into the matrix. 
D)  electrons derived from this shuttle enter the electron transport chain at UQ. 
E)  one form of glycerol-3-phosphate dehydrogenase is a flavoprotein. 
A)  there are two distinct forms of glycerol-3-phosphate dehydrogenase in cells with this shuttle. 
B)  it results in the net transfer of electrons to the electron transport chain from NADH in the cytosol. 
C)  glycerol-3-phosphate is translocated across the inner mitochondrial membrane into the matrix. 
D)  electrons derived from this shuttle enter the electron transport chain at UQ. 
E)  one form of glycerol-3-phosphate dehydrogenase is a flavoprotein.

Question 18

All are true for F1 unit of ATP synthase EXCEPT:

Accepted Answer

A)  consists of five different kinds of subunits. 
B)  catalyzes ATP hydrolysis as well as ATP synthesis. 
C)  β-subunits have catalytic sites for ATP synthesis. 
D)  α- and β-subunits are homologous. 
E)  all are true. 
A)  consists of five different kinds of subunits. 
B)  catalyzes ATP hydrolysis as well as ATP synthesis. 
C)  β-subunits have catalytic sites for ATP synthesis. 
D)  α- and β-subunits are homologous. 
E)  all are true.

Question 19

All are characteristics of the binuclear center of complex IV EXCEPT:

Accepted Answer

A)  water is released here. 
B)  CuB is a component. 
C)  Cyt a3 is a component. 
D)  Two electrons are transferred to bound O2. 
E)  Fe−S is a component. 
A)  water is released here. 
B)  CuB is a component. 
C)  Cyt a3 is a component. 
D)  Two electrons are transferred to bound O2. 
E)  Fe−S is a component.

Question 20

All are characteristics of inner mitochondrial membranes EXCEPT:

Accepted Answer

A)  contains specific transport proteins. 
B)  membrane lipids have mostly unsaturated fatty acids. 
C)  folds into cristae. 
D)  contains porin in high concentration. 
E)  all are correct. 
A)  contains specific transport proteins. 
B)  membrane lipids have mostly unsaturated fatty acids. 
C)  folds into cristae. 
D)  contains porin in high concentration. 
E)  all are correct.

Exam 20: Electron Transport and Oxidative Phosphorylation

The first half of the Q cycle results in which of the following?

Discuss Peter Mitchell's chemiosmotic hypothesis.​

All are properties of glycerol-3-phosphate dehydrogenases EXCEPT:

The malate-aspartate shuttle transfers ____ from cytosol to matrix while _____ moves from matrix to cytosol

Which of the following is a two-electron donor?

Bacteria and other prokaryotic cells have the capacity to get more ATP/glucose oxidized than eukaryotic cells because ____, so they are more efficient.

Reduction involves the ____ of electron(s), and reactions for which the standard cell potential is ____ are spontaneous under standard conditions.

Which complex reduces molecular oxygen?

Which of the following complex(es) translocate protons in the inner mitochondrial membrane?

ATP made in glycolysis and the TCA cycle is the result of ____ phosphorylation, and NADH-dependent ATP synthesis is the result of ____ phosphorylation.

All are linked to the electron-transport chain through Complex I accepting electrons from NADH EXCEPT:

Which of the following is an inhibitor of Complex IV?

Does electron transport stop if rotenone is added? Why?

All are single-electron carriers EXCEPT:

All of the following are properties of ATP synthase EXCEPT:

If an ATP synthase contains 10 c subunits, 3 α subunits and 3 β subunits, how many protons must pass through this complex for every ATP molecule synthesized (assuming that all of the protons are used for ATP synthesis)?

All are correct about the glycerophosphate shuttle EXCEPT:

All are true for F1 unit of ATP synthase EXCEPT:

All are characteristics of the binuclear center of complex IV EXCEPT:

All are characteristics of inner mitochondrial membranes EXCEPT:

The Facts of Life: Chemistry Is the Logic of Biological Phenomena

Water: the Medium of Life

Thermodynamics of Biological Systems

Amino Acids and the Peptide Bond

Proteins: Their Primary Structure and Biological Functions

Proteins: Secondary, Tertiary, and Quaternary Structure

Carbohydrates and the Glycoconjugates of Cell Surfaces

Lipids

Membranes and Membrane Transport

Nucleotides and Nucleic Acids

Structure of Nucleic Acids

Recombinant Dna, Cloning, Chimeric Genes, and Synthetic Biology

Enzymeskinetics and Specificity

Mechanisms of Enzyme Action

Enzyme Regulation

Molecular Motors

Metabolism: an Overview

Glycolysis

The Tricarboxylic Acid Cycle

Photosynthesis

Gluconeogenesis, Glycogen Metabolism, and the Pentose Phosphate Pathway

Fatty Acid Catabolism

Lipid Biosynthesis

Nitrogen Acquisition and Amino Acid Metabolism

Synthesis and Degradation of Nucleotides

Metabolic Integration and Organ Specialization

Dna Metabolism: Replication, Recombination, and Repair

Transcription and the Regulation of Gene Expression

Protein Synthesis

Completing the Protein Life Cycle: Folding, Processing, and Degradation

The Reception and Transmission of Extracellular Information

Filters

Discuss Peter Mitchell's chemiosmotic hypothesis.

The malate-aspartate shuttle transfers from cytosol to matrix while _ moves from matrix to cytosol

Reduction involves the of electron(s), and reactions for which the standard cell potential is are spontaneous under standard conditions.

ATP made in glycolysis and the TCA cycle is the result of phosphorylation, and NADH-dependent ATP synthesis is the result of phosphorylation.

All are true for F₁ unit of ATP synthase EXCEPT: