Question 1

What is the reaction catalyzed by complex III in the electron transport system?

Accepted Answer

A)  UQH2 + O2  UQ + H2O 
B)  UQH2 + complex IV+  UQ + complex IV 
C)  FADH2 + UQ  FAD + UQH2 
D)  UQH2 + cytochrome c+  UQ + cytochrome c 
A)  UQH2 + O2  UQ + H2O 
B)  UQH2 + complex IV+  UQ + complex IV 
C)  FADH2 + UQ  FAD + UQH2 
D)  UQH2 + cytochrome c+  UQ + cytochrome c

Question 2

The major purpose of the electron transport system is to

Accepted Answer

A)  reduce oxygen to water. 
B)  reoxidize NADH and use that energy to pump protons across a membrane. 
C)  produce ATP. 
D)  produce NADH for cellular respiration. 
A)  reduce oxygen to water. 
B)  reoxidize NADH and use that energy to pump protons across a membrane. 
C)  produce ATP. 
D)  produce NADH for cellular respiration.

Question 3

The structure of the electron transport system protein called cytochrome c is highly conserved in nature because the

Accepted Answer

A)  enzyme has the rare ability to bind O2 and reduce it. 
B)  protein active site contains a cofactor unique to the electron transport system. 
C)  protein is located inside the mitochondria of eukaryotic cells. 
D)  protein plays an important role in the electron transport system and in other critical cellular pathways such as apoptosis. 
A)  enzyme has the rare ability to bind O2 and reduce it. 
B)  protein active site contains a cofactor unique to the electron transport system. 
C)  protein is located inside the mitochondria of eukaryotic cells. 
D)  protein plays an important role in the electron transport system and in other critical cellular pathways such as apoptosis.

Question 4

On the left hand side of the figure,label the regions above and below the lipid membrane assuming the process occurs in mitochondria.On the right hand side,label the regions assuming the process occurs in chloroplasts.

Accepted Answer

The answer of On the left hand side of the...

Question 5

Use the structure of the oxidized coenzyme Q (ubiquinone)shown below and draw the two-electron reduced form.

Accepted Answer

The answer of Use the structure of the oxidized coenzyme...

Question 6

What is the primary fuel metabolized by the mitochondria in brown adipose tissue of hibernating animals?

Accepted Answer

A)  glucose 
B)  NADH 
C)  lipid 
D)  ATP 
A)  glucose 
B)  NADH 
C)  lipid 
D)  ATP

Question 7

How many ATPs are produced from the complete metabolism of one glucose molecule,assuming that all resulting NADH and FADH2 is used by the electron transport chain and oxidative phosphorylation to make ATP?

Accepted Answer

A)  4 
B)  16 
C)  32 
D)  102 
A)  4 
B)  16 
C)  32 
D)  102

Question 8

On the figure below label the clearly identify the positions of the three functional units of ATP synthase: the rotor,the catalytic headpiece,and the stator.

Accepted Answer

The answer of On the figure below label the clearly...

Question 9

The TCA cycle is dependent on O2 to

Accepted Answer

A)  enable the regeneration of the NAD+ by the electron transport system. 
B)  oxidize the sugar carbons to CO2. 
C)  support cellular combustion reactions. 
D)  serve as a substrate for the oxidoreductase enzymes. 
A)  enable the regeneration of the NAD+ by the electron transport system. 
B)  oxidize the sugar carbons to CO2. 
C)  support cellular combustion reactions. 
D)  serve as a substrate for the oxidoreductase enzymes.

Question 10

Which of the following is an electron carrier in the mitochondrial electron transport system?

Accepted Answer

A)  proton 
B)  water 
C)  quinone 
D)  ATP 
A)  proton 
B)  water 
C)  quinone 
D)  ATP

Question 11

Which directions across the mitochondria must H+,ATP,ADP,and Pi travel during active mitochondrial ATP synthesis?

Accepted Answer

H⁺ travels back into the mitoch

Question 12

Describe the process by which proton flow through the c subunits forces the rotation of the ATP synthase spindle in the mitochondrial membrane.Please include the roles of aspartic acid residues and the half-channels in your description.

Accepted Answer

Protons from the high concentration side

Question 13

What enzyme uses the proton motive force for its driving force?

Accepted Answer

A)  complex IV 
B)  ATP synthase 
C)  complex III 
D)  complex I 
A)  complex IV 
B)  ATP synthase 
C)  complex III 
D)  complex I

Question 14

Which process or pathway describes the coupling of the oxidation reaction of NADH with the formation of ATP?

Accepted Answer

A)  electron transport system 
B)  chemiosmotic theory 
C)  proton motive force 
D)  oxidative phosphorylation 
A)  electron transport system 
B)  chemiosmotic theory 
C)  proton motive force 
D)  oxidative phosphorylation

Question 15

Why are 2,4-dintrophenol and thermogenin referred to as uncouplers?

Accepted Answer

They uncouple the electron tra

Question 16

ATP synthesis occurs

Accepted Answer

A)  on the outer mitochondrial membrane. 
B)  at the ATP synthase complex after ADP and Pi are transported into the mitochondria. 
C)  as a result of the leakage of H+ back out of the mitochondria. 
D)  from the electron transfer reactions through complex IV. 
A)  on the outer mitochondrial membrane. 
B)  at the ATP synthase complex after ADP and Pi are transported into the mitochondria. 
C)  as a result of the leakage of H+ back out of the mitochondria. 
D)  from the electron transfer reactions through complex IV.

Question 17

Complex IV in the mitochondrial electron transport chain belongs to which enzyme class?

Accepted Answer

A)  lyase 
B)  hydrolase 
C)  transferase 
D)  oxidoreductase 
A)  lyase 
B)  hydrolase 
C)  transferase 
D)  oxidoreductase

Question 18

Label the locations of   ,   
,   ,and c,and the F0 and F1 subunits on the following ATP synthase enzyme.

Accepted Answer

Note that the @#IMG-DLM&_TB6697_11 and @#IMG-DLM&_

Question 19

Inhibitors of the electron transport system,such as cyanide (CN-)and carbon monoxide (CO),inhibit complex IV by binding to the heme iron cofactor.What is the resulting effect on oxidative phosphorylation?

Accepted Answer

A)  Electrons pass through the electron transport system, but no protons are pumped. 
B)  Protons are pumped, but no electron transport occurs. 
C)  The electron transport system occurs normally, but no ATP is synthesized. 
D)  Electron transport is disabled, and no protons are pumped. 
A)  Electrons pass through the electron transport system, but no protons are pumped. 
B)  Protons are pumped, but no electron transport occurs. 
C)  The electron transport system occurs normally, but no ATP is synthesized. 
D)  Electron transport is disabled, and no protons are pumped.

Question 20

A decrease in __________ would be LEAST likely to affect the processes of the electron transport system.

Accepted Answer

A)  oxygen concentrations in the cell 
B)  the TCA cycle activity 
C)  cellular CO2 concentrations 
D)  the concentration of cellular NADH 
A)  oxygen concentrations in the cell 
B)  the TCA cycle activity 
C)  cellular CO2 concentrations 
D)  the concentration of cellular NADH

Exam 11: Oxidative Phosphorylation

What is the reaction catalyzed by complex III in the electron transport system?

The major purpose of the electron transport system is to

The structure of the electron transport system protein called cytochrome c is highly conserved in nature because the

On the left hand side of the figure,label the regions above and below the lipid membrane assuming the process occurs in mitochondria.On the right hand side,label the regions assuming the process occurs in chloroplasts.

Use the structure of the oxidized coenzyme Q (ubiquinone)shown below and draw the two-electron reduced form.

What is the primary fuel metabolized by the mitochondria in brown adipose tissue of hibernating animals?

How many ATPs are produced from the complete metabolism of one glucose molecule,assuming that all resulting NADH and FADH2 is used by the electron transport chain and oxidative phosphorylation to make ATP?

On the figure below label the clearly identify the positions of the three functional units of ATP synthase: the rotor,the catalytic headpiece,and the stator.

The TCA cycle is dependent on O2 to

Which of the following is an electron carrier in the mitochondrial electron transport system?

Which directions across the mitochondria must H+,ATP,ADP,and Pi travel during active mitochondrial ATP synthesis?

Describe the process by which proton flow through the c subunits forces the rotation of the ATP synthase spindle in the mitochondrial membrane.Please include the roles of aspartic acid residues and the half-channels in your description.

What enzyme uses the proton motive force for its driving force?

Which process or pathway describes the coupling of the oxidation reaction of NADH with the formation of ATP?

Why are 2,4-dintrophenol and thermogenin referred to as uncouplers?

ATP synthesis occurs

Complex IV in the mitochondrial electron transport chain belongs to which enzyme class?

Label the locations of , , ,and c,and the F0 and F1 subunits on the following ATP synthase enzyme.

Inhibitors of the electron transport system,such as cyanide (CN-)and carbon monoxide (CO),inhibit complex IV by binding to the heme iron cofactor.What is the resulting effect on oxidative phosphorylation?

A decrease in __________ would be LEAST likely to affect the processes of the electron transport system.

Principles of Biochemistry

Physical Biochemistry: Energy Conversion,water,and Membranes

Nucleic Acid Structure and Function

Protein Structure

Methods in Protein Biochemistry

Protein Function

Enzyme Mechanisms

Cell Signaling Systems

Glycolysis: a Paradigm of Metabolic Regulation

The Citrate Cycle

Photosynthesis

Carbohydrate Structure and Function

Carbohydrate Metabolism

Lipid Structure and Function

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Metabolic Integration

Dna Replication, repair, and Recombination

Rna Synthesis, processing, and Gene Silencing

Protein Synthesis, posttranslational Modification, and Transport

Gene Regulation

Filters

How many ATPs are produced from the complete metabolism of one glucose molecule,assuming that all resulting NADH and FADH₂ is used by the electron transport chain and oxidative phosphorylation to make ATP?

The TCA cycle is dependent on O₂ to

Which directions across the mitochondria must H⁺,ATP,ADP,and P_i travel during active mitochondrial ATP synthesis?

Label the locations of , , ,and c,and the F₀ and F₁ subunits on the following ATP synthase enzyme.

Inhibitors of the electron transport system,such as cyanide (CN^-)and carbon monoxide (CO),inhibit complex IV by binding to the heme iron cofactor.What is the resulting effect on oxidative phosphorylation?