View the step-by-step solution to:

Multiple-Choice Questions 1) What is the term for metabolic pathways that release stored energy by breaking down complex molecules?

Multiple-Choice Questions

1)

What is the term for metabolic pathways that release stored energy by breaking down complex molecules?
A)

anabolic pathways
B)

catabolic pathways
C)

fermentation pathways
D)

thermodynamic pathways
E)

bioenergetic pathways
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

2)

The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction
A)

gains electrons and gains energy.
B)

loses electrons and loses energy.
C)

gains electrons and loses energy.
D)

loses electrons and gains energy.
E)

neither gains nor loses electrons, but gains or loses energy.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

3)

When electrons move closer to a more electronegative atom, what happens?
A)

Energy is released.
B)

Energy is consumed.
C)

The more electronegative atom is reduced.
D)

The more electronegative atom is oxidized.
E)

A and C are correct.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension
4)




Why does the oxidation of organic compounds by molecular oxygen to produce CO2 and water release free energy?
A)

The covalent bonds in organic molecules are higher energy bonds than those in water and carbon dioxide.
B)

Electrons are being moved from atoms that have a lower affinity for electrons (such as C) to atoms with a higher affinity for electrons (such as O).
C)

The oxidation of organic compounds can be used to make ATP.
D)

The electrons have a higher potential energy when associated with water and CO2 than they do in organic compounds.
E)

The covalent bond in O2 is unstable and easily broken by electrons from organic molecules.

Topic:

Concept 9.1
Skill:

Knowledge/Comprehension
5)

Which of the following statements describes the results of this reaction?
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
A)

C6H12O6 is oxidized and O2 is reduced.
B)

O2 is oxidized and H2O is reduced.
C)

CO2 is reduced and O2 is oxidized.
D)

C6H12O6 is reduced and CO2 is oxidized.
E)

O2 is reduced and CO2 is oxidized.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

6)

When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction reaction, the molecule becomes
A)

dehydrogenated.
B)

hydrogenated.
C)

oxidized.
D)

reduced.
E)

an oxidizing agent.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

7)

When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a hydrogen ion) the molecule becomes
A)

hydrogenated.
B)

oxidized.
C)

reduced.
D)

redoxed.
E)

a reducing agent.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

8)

Which of the following statements describes NAD+?
A)

NAD+ is reduced to NADH during both glycolysis and the citric acid cycle.
B)

NAD+ has more chemical energy than NADH.
C)

NAD+ is reduced by the action of hydrogenases.
D)

NAD+ can donate electrons for use in oxidative phosphorylation.
E)

In the absence of NAD+, glycolysis can still function.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension
9)

Where does glycolysis takes place?
A)

mitochondrial matrix
B)

mitochondrial outer membrane
C)

mitochondrial inner membrane
D)

mitochondrial intermembrane space
E)

cytosol

Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

10)

The ATP made during glycolysis is generated by
A)

substrate-level phosphorylation.
B)

electron transport.
C)

photophosphorylation.
D)

chemiosmosis.
E)

oxidation of NADH to NAD+.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

11)

The oxygen consumed during cellular respiration is involved directly in which process or event?
A)

glycolysis
B)

accepting electrons at the end of the electron transport chain
C)

the citric acid cycle
D)

the oxidation of pyruvate to acetyl CoA
E)

the phosphorylation of ADP to form ATP
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension
12)




Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent?
A)

electron transport
B)

glycolysis
C)

the citric acid cycle
D)

oxidative phosphorylation
E)

chemiosmosis
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

13)

An electron loses potential energy when it
A)

shifts to a less electronegative atom.
B)

shifts to a more electronegative atom.
C)

increases its kinetic energy.
D)

increases its activity as an oxidizing agent.
E)

attaches itself to NAD+.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension
14)

Why are carbohydrates and fats considered high energy foods?
A)

They have a lot of oxygen atoms.
B)

They have no nitrogen in their makeup.
C)

They can have very long carbon skeletons.
D)

They have a lot of electrons associated with hydrogen.
E)

They are easily reduced.
Topic:

Concept 9.1
Skill:

Knowledge/Comprehension

Refer to Figure 9.1 to answer the following questions.

Figure 9.1 illustrates some of the steps (reactions) of glycolysis in their proper sequence. Each step is lettered. Use these letters to answer the questions.



Figure 9.1

15)

Which step shows a split of one molecule into two smaller molecules?
Topic:

Concept 9.2
Skill:

Application/Analysis

16)

In which step is an inorganic phosphate added to the reactant?
Topic:

Concept 9.2
Skill:

Application/Analysis

17)

In which reaction does an intermediate pathway become oxidized?
Topic:

Concept 9.2
Skill:

Application/Analysis
18)

Which step involves an endergonic reaction?
Topic:

Concept 9.2
Skill:

Application/Analysis

19)

Which step consists of a phosphorylation reaction in which ATP is the phosphate source?
Topic:

Concept 9.2
Skill:

Application/Analysis

20)

Substrate-level phosphorylation accounts for approximately what percentage of the ATP formed during glycolysis?
A)

0%
B)

2%
C)

10%
D)

38%
E)

100%
Topic:

Concept 9.2
Skill:

Application/Analysis

21)

During glycolysis, when glucose is catabolized to pyruvate, most of the energy of glucose is
A)

transferred to ADP, forming ATP.
B)

transferred directly to ATP.
C)

retained in the pyruvate.
D)

stored in the NADH produced.
E)

used to phosphorylate fructose to form fructose-6-phosphate.
Topic:

Concept 9.2
Skill:

Knowledge/Comprehension

22)

In addition to ATP, what are the end products of glycolysis?
A)

CO2 and H2O
B)

CO2 and pyruvate
C)

NADH and pyruvate
D)

CO2 and NADH
E)

H2O, FADH2, and citrate
Topic:

Concept 9.2
Skill:

Knowledge/Comprehension
23)

The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mole and the free energy for the reduction of NAD+ to NADH is +53 kcal/mole. Why are only two molecules of NADH formed during glycolysis when it appears that as many as a dozen could be formed?
A)

Most of the free energy available from the oxidation of glucose is used in the production of ATP in glycolysis.
B)

Glycolysis is a very inefficient reaction, with much of the energy of glucose released as heat.
C)

Most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis.
D)

There is no CO2 or water produced as products of glycolysis.
E)

Glycolysis consists of many enzymatic reactions, each of which extracts some energy from the glucose molecule.
Topic:

Concept 9.2
Skill:

Synthesis/Evaluation
24)




Starting with one molecule of glucose, the "net" products of glycolysis are
A)

2 NAD+, 2 H+, 2 pyruvate, 2 ATP, and 2 H2O.
B)

2 NADH, 2 H+, 2 pyruvate, 2 ATP, and 2 H2O.
C)

2 FADH2, 2 pyruvate, 4 ATP, and 2 H2O.
D)

6 CO2, 6 H2O, 2 ATP, and 2 pyruvate.
E)

6 CO2, 6 H2O, 36 ATP, and 2 citrate.

Topic:

Concept 9.2
Skill:

Knowledge/Comprehension

25)

In glycolysis, for each molecule of glucose oxidized to pyruvate
A)

2 molecules of ATP are used and 2 molecules of ATP are produced.
B)

2 molecules of ATP are used and 4 molecules of ATP are produced.
C)

4 molecules of ATP are used and 2 molecules of ATP are produced.
D)

2 molecules of ATP are used and 6 molecules of ATP are produced.
E)

6 molecules of ATP are used and 6 molecules of ATP are produced.
Topic:

Concept 9.2
Skill:

Knowledge/Comprehension

26)

A molecule that is phosphorylated
A)

has been reduced as a result of a redox reaction involving the loss of an inorganic phosphate.
B)

has a decreased chemical reactivity; it is less likely to provide energy for cellular work.
C)

has been oxidized as a result of a redox reaction involving the gain of an inorganic phosphate.
D)

has an increased chemical reactivity; it is primed to do cellular work.
E)

has less energy than before its phosphorylation and therefore less energy for cellular work.
Topic:

Concept 9.2
Skill:

Synthesis/Evaluation
27)

Which kind of metabolic poison would most directly interfere with glycolysis?
A)

an agent that reacts with oxygen and depletes its concentration in the cell
B)

an agent that binds to pyruvate and inactivates it
C)

an agent that closely mimics the structure of glucose but is not metabolized
D)

an agent that reacts with NADH and oxidizes it to NAD+
E)

an agent that blocks the passage of electrons along the electron transport chain
Topic:

Concept 9.2
Skill:

Application/Analysis
28)




Why is glycolysis described as having an investment phase and a payoff phase?
A)

It both splits molecules and assembles molecules.
B)

It attaches and detaches phosphate groups.
C)

It uses glucose and generates pyruvate.
D)

It shifts molecules from cytosol to mitochondrion.
E)

It uses stored ATP and then forms a net increase in ATP.
Topic:

Concept 9.2
Skill:

Knowledge/Comprehension

Use the following information to answer the next questions.

In the presence of oxygen, the three-carbon compound pyruvate can be catabolized in the citric acid cycle. First, however, the pyruvate 1) loses a carbon, which is given off as a molecule of CO2, 2) is oxidized to form a two-carbon compound called acetate, and 3) is bonded to coenzyme A.

29)

These three steps result in the formation of
A)

acetyl CoA, O2, and ATP.
B)

acetyl CoA, FADH2, and CO2.
C)

acetyl CoA, FAD, H2, and CO2.
D)

acetyl CoA, NADH, H+, and CO2.
E)

acetyl CoA, NAD+, ATP, and CO2.
Topic:

Concept 9.3
Skill:

Application/Analysis

30)

Why is coenzyme A, a sulfur containing molecule derived from a B vitamin, added?
A)

because sulfur is needed for the molecule to enter the mitochondrion
B)

in order to utilize this portion of a B vitamin which would otherwise be a waste product from another pathway
C)

to provide a relatively unstable molecule whose acetyl portion can readily bind to oxaloacetate
D)

because it drives the reaction that regenerates NAD+
E)

in order to remove one molecule of CO2
Topic:

Concept 9.3
Skill:

Synthesis/Evaluation
31)

How does pyruvate enter the mitochondrion?
A)

active transport
B)

diffusion
C)

facilitated diffusion
D)

through a channel
E)

through a pore
Topic:

Concept 9.3
Skill:

Knowledge/Comprehension
32)




Which of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the removal of a carbon (CO2) from one molecule of pyruvate?
A)

lactate
B)

glyceraldehydes-3-phosphate
C)

oxaloacetate
D)

acetyl CoA
E)

citrate
Topic:

Concept 9.3
Skill:

Knowledge/Comprehension

33)

During cellular respiration, acetyl CoA accumulates in which location?
A)

cytosol
B)

mitochondrial outer membrane
C)

mitochondrial inner membrane
D)

mitochondrial intermembrane space
E)

mitochondrial matrix

Topic:

Concept 9.3
Skill:

Knowledge/Comprehension

34)

How many carbon atoms are fed into the citric acid cycle as a result of the oxidation of one molecule of pyruvate?
A)

2
B)

4
C)

6
D)

8
E)

10

Recently Asked Questions

Why Join Course Hero?

Course Hero has all the homework and study help you need to succeed! We’ve got course-specific notes, study guides, and practice tests along with expert tutors.

-

Educational Resources
  • -

    Study Documents

    Find the best study resources around, tagged to your specific courses. Share your own to gain free Course Hero access.

    Browse Documents
  • -

    Question & Answers

    Get one-on-one homework help from our expert tutors—available online 24/7. Ask your own questions or browse existing Q&A threads. Satisfaction guaranteed!

    Ask a Question