Deck 10: Chemotrophic Energy Metabolism: Aerobic Respiration

Question 1

According to your text, in which of the following steps of the TCA cycle is NADH/FADH2 NOT produced?

A)TCA- 8
B)TCA- 4
C)TCA- 6
D)TCA- 2
E)TCA- 3

Answer 1

D

Question 2

The TCA cycle and glyoxylate cycle are similar in many respects. Which of the following statements accurately describes these cycles?

A)The glyoxylate cycle has only a single decarboxylating reaction.
B)The glyoxylate cycle is used by some organisms to synthesize proteins.
C)The TCA and glyoxylate cycles both occur in the mitochondrion.
D)Both cycles are catabolic in function.
E)In the glyoxylate cycle, two acetyl CoA molecules are used to generate succinate.

Answer 2

E

Question 3

Multiple protein complexes associated with the cellular respiration are known as

A)synthesomes.
B)respirasomes.
C)Fe- S centers.
D)Q cycles.
E)chemiosmotic coupling complexes.

Answer 3

B

Question 4

Of the following electron carriers of the electron transport system, which transfers protons in addition to electrons?

A)iron- copper proteins
B)cytochrome b
C)cytochrome a
D)coenzyme Q
E)iron- sulfur proteins

Question 5

Because the TCA cycle is associated with degradation and synthesis, the pathway is said to be

A)amphipathic.
B)amphibolic.
C)anabolic.
D)catabolic.
E)bipolar.

Question 6

Which of the following would NOT be used as a final electron acceptor in anaerobic respiration?

A)sulfur
B)oxygen
C)nitrogen
D)iron
E)protons

Question 7

Which of the following is NOT one of the major transport systems of the inner mitochondrial membrane?

A)sodium- potassium pump
B)pyruvate carrier cotransport
C)ATP- ADP carrier exchange
D)dicarboxylate carriers
E)tricarboxylate carriers

Question 8

Which of the following molecules is NOT a carrier of electrons in the electron transport system (ETS)?

A)coenzyme Q
B)flavoproteins
C)copper- nickel compounds
D)iron- sulfur proteins
E)cytochromes

Question 9

When utilizing fats as an energy source, the glycerol portion enters _, when it has been converted to .

A)TCA cycle; pyruvate
B)electron transport; CoQ
C)glycolysis; fructose- 6- phosphate
D)glycolysis; dihydroxyacetone phosphate
E)TCA cycle; acetyl CoA

Question 10

Pyruvate dehydrogenase is regulated by all EXCEPT

A)AMP.
B)ATP.
C)CO₂.
D)NADH.
E)acetyl CoA.

Question 11

The sequential process of fatty acid catabolism to acetyl CoA is called

A)the glyoxylate cycle.
B)fi- oxidation.
C)oxidative phosphorylation.
D)hydrogenation.
E)the Cori cycle.

Question 12

The chemiosmotic model of ATP synthesis is based on several lines of experimental evidence. Which of the following statements is NOT correct experimental evidence to support the chemiosmotic model?

A)Oxidative phosphorylation does not require a membrane- enclosed compartment.
B)The proton gradient established by electron transport has enough energy to drive ATP synthesis.
C)Uncoupling agents abolish both the proton gradient and ATP synthesis.
D)Electron transport causes protons to be pumped out of the mitochondrial matrix.
E)Artificial proton gradients established by addition of acid can drive ATP synthesis in the absence of electron transport.

Question 13

In prokaryotes, aerobic respiration generates ATP molecules.

A)15
B)2
C)38
D)42
E)0

Question 14

Which of the following is NOT a product of the TCA cycle?

A)NADH
B)ATP
C)acetyl CoA
D)carbon dioxide (CO₂)
E)FADH2

Question 15

Of the following enzymes associated with the TCA cycle, which of the following enzymes is NOT under allosteric regulation?

A)malate dehydrogenase
B)pyruvate dehydrogenase complex
C)isocitrate dehydrogenase
D)a- ketoglutarate dehydrogenase
E)fumarate hydratase

Question 16

In electron transport, which respiratory complex is NOT involved in the flow of electrons from NADH?

A)complex IV
B)complex I
C)complex III
D)complex II
E)all of the above

Question 17

The Q cycle

A)accounts for the generation of superoxide.
B)mediates the transfer of electrons to oxygen.
C)allows for the movement of protons without additional electrons.
D)is associated with complex I.
E)all of the above

Question 18

Which of the following statements is NOT true of the TCA cycle?

A)Acetate enters the TCA cycle and joins a four- carbon acceptor molecule to form citrate.
B)Decarboxylation occurs at two locations in the TCA cycle.
C)FAD is an electron acceptor in the cycle.
D)ATP/GTP is generated at one point by substrate- level phosphorylation.
E)Oxidation occurs at three steps in the TCA cycle.

Question 19

Why are mitochondria so prevalent in skeletal muscle?

A)They are needed to provide energy for muscle contraction.
B)The flow of blood is greatest in skeletal muscle.
C)They are needed to repair damaged tissue that accumulates during exercise.
D)They give the muscle enough elasticity to contract.
E)Bones and muscles require a great deal of energy to prevent them from separating.

Question 20

Crista junctions

A)limit the movement of products between the intracristae and intermembrane spaces.
B)are large pores.
C)are associated with the thylakoid membrane system.
D)are associated with the movement of materials from the cytosol into the mitochondrion.
E)contain the mitochondrial DNA.

Question 21

In electron transport, which respiratory complex is NOT involved in the flow of electrons from FADH2?

A)complex III
B)complex I
C)complex II
D)complex IV
E)All of the above

Question 22

As pyruvate is prepared for the TCA cycle, it undergoes a process of

A)CoQ reproduction.
B)oxidative decarboxylation.
C)reductive carboxylation.
D)oxidative carboxylation.
E)reductive decarboxylation.

Question 23

Which of the following processes is associated with the outer mitochondrial membrane?

A)phospholipid synthesis
B)fi- oxidation of fats
C)metabolite transport
D)transcription
E)ATP synthesis

Question 24

NADH concentrations serve to regulate oxidative decarboxylation and the TCA cycle. Which of the following enzymes is NOT regulated by NADH?

A)malate dehydrogenase
B)pyruvate dehydrogenase
C)isocitrate dehydrogenase
D)succinate dehydrogenase
E)a ketoglutarate dehydrogenase

Question 25

Which molecule is incorrectly matched with the number of carbon atoms it possesses?

A)isocitrate- 6
B)citrate- 6
C)malate- 5
D)acetyl CoA- 2
E)alpha ketoglutarate- 5

Question 26

Of the carrier molecules in the electron transport chain, which has heme as part of its prosthetic group?

A)copper- containing cytochromes
B)cytochromes
C)flavoproteins
D)coenzyme Q
E)iron- sulfur proteins

Question 27

Of the following sequences, which shows the correct molecules through which electrons flow when delivered to the electron transport system by NADH?

A)complex I, coenzyme Q, complex III, complex IV, oxygen
B)complex I, coenzyme Q, complex IV, cytochrome c, oxygen
C)complex II, coenzyme Q, complex III, complex IV, oxygen
D)complex I, cytochrome c, complex III, coenzyme Q, complex IV, oxygen
E)complex I, coenzyme Q, complex III, cytochrome c, complex IV, oxygen

Question 28

In eukaryotes, pyruvate is converted to acetyl CoA

A)in the intermembrane space.
B)in the cellular cytosol.
C)in the mitochondrial matrix.
D)when passing through the mitochondrial outer membrane.
E)when passing the mitochondrial cristae.

Question 29

Which of the numbered respiratory complexes is NOT correctly paired with its name?

A)complex II: succinate- coenzyme Q oxidoreductase complex
B)complex III: coenzyme Q- cytochrome c oxidoreductase complex
C)complex I: NADH dehydrogenase complex
D)complex IV: cytochrome c reductase complex
E)none of the above

Question 30

is the oxidation- driven flow of electrons, through or within a membrane, from reduced coenzymes to an electron acceptor. It is usually accompanied by the generation of ATP.

Question 31

The overall efficiency of aerobic respiration in eukaryotes is about

A)10%.
B)75%.
C)25%.
D)100%.
E)55%.

Question 32

During which of the following steps of the TCA cycle does substrate- level phosphorylation take place?

A)TCA- 3
B)TCA- 2
C)TCA- 4
D)TCA- 6
E)TCA- 5

Question 33

The reduction of NAD+ to NADH (and H+)occurs both in the and in the
of the _ .

Question 34

fi- oxidation

A)is a process used to oxidize fatty acids.
B)is a process used to digest some polysaccharides.
C)is the second step in the oxidation of glucose.
D)occurs in the cytoplasm.
E)both B and C