Question 1

Bacteria with superoxide dismutase (SOD)can usually grow anaerobically.

Accepted Answer

A) True 
 B)False

Question 2

White muscle is exhausted faster than red muscle because white muscles

Accepted Answer

A) rely only on anaerobic glycolysis for energy. 
B) have fewer mitochondria. 
C) have no mitochondria. 
D) cannot make ATP. 
A) rely only on anaerobic glycolysis for energy. 
B) have fewer mitochondria. 
C) have no mitochondria. 
D) cannot make ATP.

Question 3

Mitochondria are about the size of an E.coli cell.

Accepted Answer

A) True 
 B)False

Question 4

There are some eukaryotic species that do not have mitochondria.

Accepted Answer

A) True 
 B)False

Question 5

In complex III,the Q cycle describes two cycles.One cycle begins with reduction of quinone (Q),and the other cycle begins with the reduction of semiquinone intermediate.

Accepted Answer

A) True 
 B)False

Question 6

Menaquinone has greater reduction potential than FAD.

Accepted Answer

A) True 
 B)False

Question 7

The reactions in complex II release very little free energy and do not contribute directly to the proton concentration gradient.

Accepted Answer

A) True 
 B)False

Question 8

Complex II participates in both the electron transport chain and the citric acid cycle.

Accepted Answer

A) True 
 B)False

Question 9

White muscle cells contain fewer mitochondria than red muscle cells,so they rely on anaerobic glycolysis for energy needs.

Accepted Answer

A) True 
 B)False

Question 10

The inner mitochondrial membrane contributes to the formation of a proton gradient mainly because it

Accepted Answer

A) contains ATP synthase complex. 
B) is the location of specific transporter proteins. 
C) is a barrier to protons. 
D) is not rich in proteins. 
E) is rich in proteins. 
A) contains ATP synthase complex. 
B) is the location of specific transporter proteins. 
C) is a barrier to protons. 
D) is not rich in proteins. 
E) is rich in proteins.

Question 11

The enzyme complexes associated with oxidative phosphorylation and the electron transport chain can be classified as ________ proteins.

Accepted Answer

A) integral membrane 
B) peripheral membrane 
C) lipid-anchored membrane 
D) water-soluble 
E) Both A and C 
A) integral membrane 
B) peripheral membrane 
C) lipid-anchored membrane 
D) water-soluble 
E) Both A and C

Question 12

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

Accepted Answer

A) True 
 B)False

Question 13

The presence of superoxide dismutase (SOD)in mammalian cells can be harmful or beneficial,depending on the location.

Accepted Answer

A) True 
 B)False

Question 14

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 15

Which statement is true about two reactions that are coupled?

Accepted Answer

A) One reaction will normally not occur without the other. 
B) One is always exergonic and the other is always endergonic. 
C) Only oxidation-reduction reactions can be coupled. 
D) Coupled reactions are always driven by the ATP to ADP conversion. 
A) One reaction will normally not occur without the other. 
B) One is always exergonic and the other is always endergonic. 
C) Only oxidation-reduction reactions can be coupled. 
D) Coupled reactions are always driven by the ATP to ADP conversion.

Question 16

Heat can be generated in the brown adipose tissue of hibernating mammals due to ________.

Accepted Answer

A) increased ATP production by ATP synthase 
B) uncoupling by thermogenin 
C) a greater pH gradient across the inner mitochondrial membrane by complex IV 
D) insufficient NADH production during the citric acid cycle due to less active pyruvate translocase. 
A) increased ATP production by ATP synthase 
B) uncoupling by thermogenin 
C) a greater pH gradient across the inner mitochondrial membrane by complex IV 
D) insufficient NADH production during the citric acid cycle due to less active pyruvate translocase.

Question 17

In the presence of an uncoupler,more substrate can be oxidized.

Accepted Answer

A) True 
 B)False

Question 18

In eukaryotes 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.

Question 19

The inner membrane of mitochondria is permeable to ________,but not to ________.

Accepted Answer

A) protons;water 
B) cations;anions 
C) charged molecules;uncharged molecules 
D) uncharged molecules;charged molecules 
A) protons;water 
B) cations;anions 
C) charged molecules;uncharged molecules 
D) uncharged molecules;charged molecules

Question 20

In the presence of oxygen and in the absence of ADP,what occurs if the uncoupler 2,4-dinitrophenol is added to a suspension of normal mitochondria five minutes after an oxidizable substrate has been added?

Accepted Answer

A) The substrate will be oxidized until the addition of the 2,4-dinitrophenol,which blocks further oxidation. 
B) There is no effect;oxidation of the substrate continues at the same rate before and after the addition of 2,4-dinitrophenol. 
C) The substrate cannot be oxidized either with or without 2,4-dinitrophenol unless ADP is also present. 
D) Oxidation of the substrate does not occur until the 2,4-dinitrophenol is added.Afterward,oxidation proceeds rapidly until all of the substrate is consumed. 
A) The substrate will be oxidized until the addition of the 2,4-dinitrophenol,which blocks further oxidation. 
B) There is no effect;oxidation of the substrate continues at the same rate before and after the addition of 2,4-dinitrophenol. 
C) The substrate cannot be oxidized either with or without 2,4-dinitrophenol unless ADP is also present. 
D) Oxidation of the substrate does not occur until the 2,4-dinitrophenol is added.Afterward,oxidation proceeds rapidly until all of the substrate is consumed.

Exam 14: Electron Transport and Atp Synthesis

Bacteria with superoxide dismutase (SOD)can usually grow anaerobically.

White muscle is exhausted faster than red muscle because white muscles

Mitochondria are about the size of an E.coli cell.

There are some eukaryotic species that do not have mitochondria.

In complex III,the Q cycle describes two cycles.One cycle begins with reduction of quinone (Q),and the other cycle begins with the reduction of semiquinone intermediate.

Menaquinone has greater reduction potential than FAD.

The reactions in complex II release very little free energy and do not contribute directly to the proton concentration gradient.

Complex II participates in both the electron transport chain and the citric acid cycle.

White muscle cells contain fewer mitochondria than red muscle cells,so they rely on anaerobic glycolysis for energy needs.

The inner mitochondrial membrane contributes to the formation of a proton gradient mainly because it

The enzyme complexes associated with oxidative phosphorylation and the electron transport chain can be classified as ________ proteins.

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

The presence of superoxide dismutase (SOD)in mammalian cells can be harmful or beneficial,depending on the location.

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

Which statement is true about two reactions that are coupled?

Heat can be generated in the brown adipose tissue of hibernating mammals due to ________.

In the presence of an uncoupler,more substrate can be oxidized.

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

The inner membrane of mitochondria is permeable to ________,but not to ________.

In the presence of oxygen and in the absence of ADP,what occurs if the uncoupler 2,4-dinitrophenol is added to a suspension of normal mitochondria five minutes after an oxidizable substrate has been added?

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

Filters

The inner membrane of mitochondria is permeable to ,but not to .