Question 1

Give the chemical reaction between the mitochondrial electron transport system's original electron donor and final electron acceptor.

Accepted Answer

NADH + H⁺

Question 2

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 3

What type of transport is illustrated by the mitochondrial ATP/ADP translocase?

Accepted Answer

A)  symporter 
B)  antiporter 
C)  facilitated diffusion 
D)  primary active transporter 
A)  symporter 
B)  antiporter 
C)  facilitated diffusion 
D)  primary active transporter

Question 4

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 5

What would happen to a mutated ATP synthase enzyme where the proton binding aspartate residue on the c subunits was mutated to an alanine?

Accepted Answer

A)  The enzyme would make ATP as normal in the presence of a proton gradient. 
B)  The enzyme would not make ATP in the presence of a proton gradient. 
C)  The enzyme would make ATP without the need for a proton gradient. 
D)  The rotor would rotate in response to a proton gradient, but no ATP would be made. 
A)  The enzyme would make ATP as normal in the presence of a proton gradient. 
B)  The enzyme would not make ATP in the presence of a proton gradient. 
C)  The enzyme would make ATP without the need for a proton gradient. 
D)  The rotor would rotate in response to a proton gradient, but no ATP would be made.

Question 6

The last enzyme in the electron transport system, where O2 is reduced to water, is called

Accepted Answer

A)  NADH-ubiquinone oxidoreductase. 
B)  ATP synthase. 
C)  ubiquinone cytochrome c oxidoreductase. 
D)  cytochrome c oxidase. 
A)  NADH-ubiquinone oxidoreductase. 
B)  ATP synthase. 
C)  ubiquinone cytochrome c oxidoreductase. 
D)  cytochrome c oxidase.

Question 7

Which is NOT involved in the transfer of reducing equivalents from succinate to molecular oxygen (O2)?

Accepted Answer

A)  cytochrome c 
B)  coenzyme Q 
C)  complex I 
D)  complex II 
A)  cytochrome c 
B)  coenzyme Q 
C)  complex I 
D)  complex II

Question 8

As electrons from NADH pass through the electron transport system,

Accepted Answer

A)  the oxidized form of ADP is reduced to ATP. 
B)  the reduction potential of the mitochondria becomes more thermodynamically favorable. 
C)  the resulting electron gradient is used to make ATP. 
D)  protons are pumped across the mitochondrial membrane to create a pH gradient. 
A)  the oxidized form of ADP is reduced to ATP. 
B)  the reduction potential of the mitochondria becomes more thermodynamically favorable. 
C)  the resulting electron gradient is used to make ATP. 
D)  protons are pumped across the mitochondrial membrane to create a pH gradient.

Question 9

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 10

Brown adipose tissue is brown in color because of

Accepted Answer

A)  increased levels of thermogenin, or uncoupling protein. 
B)  increased muscle fiber content. 
C)  increased numbers of mitochondria. 
D)  decreased levels of lipid. 
A)  increased levels of thermogenin, or uncoupling protein. 
B)  increased muscle fiber content. 
C)  increased numbers of mitochondria. 
D)  decreased levels of lipid.

Question 11

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 12

List the common enzyme names of the major enzyme complexes in the oxidative phosphorylation pathway, which are required to couple NADH oxidation with ATP synthesis.

Accepted Answer

Complex I (NADH-ubiquinone oxi

Question 13

The ultimate electron acceptor of the mitochondrial electron transport system is

Accepted Answer

A)  O2. 
B)  NADH. 
C)  H2O. 
D)  cytochrome c. 
A)  O2. 
B)  NADH. 
C)  H2O. 
D)  cytochrome c.

Question 14

How many ATPs are obtained from one acetyl-CoA run once through the TCA cycle, assuming that all resulting NADH and FADH2 is used by the electron transport chain and oxidative phosphorylation to make ATP?

Accepted Answer

A)  6.5 
B)  9 
C)  10 
D)  11 
A)  6.5 
B)  9 
C)  10 
D)  11

Question 15

Add to the malate-aspartate shuttle scheme below the missing reactant and products a, b, c, and
d.

Accepted Answer

The answer of Add to the malate-aspartate shuttle scheme below...

Question 16

The role of brown adipose tissue is to

Accepted Answer

A)  efficiently generate ATP from fat tissue. 
B)  metabolize excess fat calories. 
C)  store excess calories as fat. 
D)  generate heat for the organism. 
A)  efficiently generate ATP from fat tissue. 
B)  metabolize excess fat calories. 
C)  store excess calories as fat. 
D)  generate heat for the organism.

Question 17

Which tissue types are affected the most by inherited mitochondrial disorders?

Accepted Answer

A)  those tissues with the highest levels of mitochondria and high levels of activity 
B)  heart tissue 
C)  liver tissue 
D)  those tissues with the lowest levels of mitochondria 
A)  those tissues with the highest levels of mitochondria and high levels of activity 
B)  heart tissue 
C)  liver tissue 
D)  those tissues with the lowest levels of mitochondria

Question 18

Which animal would have the lowest levels of brown adipose tissue?

Accepted Answer

A)  newborn human 
B)  hibernating squirrel 
C)  migrating duck 
D)  polar bear 
A)  newborn human 
B)  hibernating squirrel 
C)  migrating duck 
D)  polar bear

Question 19

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

Accepted Answer

They uncouple the electron tra

Question 20

Which part of the native ATP synthase enzyme is stationary and does NOT rotate during ATP synthesis?

Accepted Answer

A)  the rotor 
B)  the circle of c subunits 
C)  the central $\gamma$ subunit connecting the rotor to the catalytic headpiece 
D)  the catalytic headpiece 
A)  the rotor 
B)  the circle of c subunits 
C)  the central $\gamma$ subunit connecting the rotor to the catalytic headpiece 
D)  the catalytic headpiece

Exam 11: Oxidative Phosphorylation

Give the chemical reaction between the mitochondrial electron transport system's original electron donor and final electron acceptor.

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

What type of transport is illustrated by the mitochondrial ATP/ADP translocase?

The major purpose of the electron transport system is to

What would happen to a mutated ATP synthase enzyme where the proton binding aspartate residue on the c subunits was mutated to an alanine?

The last enzyme in the electron transport system, where O2 is reduced to water, is called

Which is NOT involved in the transfer of reducing equivalents from succinate to molecular oxygen (O2)?

As electrons from NADH pass through the electron transport system,

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

Brown adipose tissue is brown in color because of

The TCA cycle is dependent on O2 to

List the common enzyme names of the major enzyme complexes in the oxidative phosphorylation pathway, which are required to couple NADH oxidation with ATP synthesis.

The ultimate electron acceptor of the mitochondrial electron transport system is

How many ATPs are obtained from one acetyl-CoA run once through the TCA cycle, assuming that all resulting NADH and FADH2 is used by the electron transport chain and oxidative phosphorylation to make ATP?

Add to the malate-aspartate shuttle scheme below the missing reactant and products a, b, c, and d.

The role of brown adipose tissue is to

Which tissue types are affected the most by inherited mitochondrial disorders?

Which animal would have the lowest levels of brown adipose tissue?

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

Which part of the native ATP synthase enzyme is stationary and does NOT rotate during ATP synthesis?

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

The last enzyme in the electron transport system, where O₂ is reduced to water, is called

Which is NOT involved in the transfer of reducing equivalents from succinate to molecular oxygen (O₂)?

The TCA cycle is dependent on O₂ to

How many ATPs are obtained from one acetyl-CoA run once through the TCA cycle, assuming that all resulting NADH and FADH₂ is used by the electron transport chain and oxidative phosphorylation to make ATP?