Deck 8: How Cells Make Atp: Energy-Releasing Pathways

Question 1

During chemiosmosis, __________ are transferred from NADH and FADH₂ to electron acceptor molecules, and the energy released is used to create a(n) __________ gradient across the inner mitochondrial membrane.

A) protons; electron
B) electrons; proton
C) ATP molecules; ADP molecule
D) ADP molecules; ATP molecule
E) water molecules; oxygen

Answer 1

B

Question 2

Which of the following is an end product of glycolysis?

A) ATP
B) NAD⁺
C) FADH₂
D) acetyl CoA
E) CO₂

Answer 2

A

Question 3

Cellular respiration is most accurately described as a(n) __________ process.

A) anabolic
B) catabolic
C) metabolic
D) endergonic
E) fermentative

Answer 3

B

Question 4

The transfer of electrons from glucose to oxygen during aerobic respiration takes place in a stepwise fashion through a number of intermediates rather than by direct transfer.This is because:

A) it is chemically impossible to transfer electrons directly from glucose to oxygen.
B) the chemical intermediates donate some of their electrons in order to increase the electron pool.
C) the energy of the electrons can be used to make ADP.
D) the energy of the electrons can be used to make ATP.
E) the energy of the protons can be used to make ATP.

Question 5

Aerobic respiration is classified as:

A) a synthesis reaction.
B) a hydrolysis reaction.
C) a redox process.
D) a polymerization reaction.
E) an anabolic process.

Question 6

Which of the following is not one of the starting materials of the citric acid?

A) FAD
B) NAD⁺
C) acetyl CoA
D) ATP
E) H₂O

Question 7

The overall reaction for the aerobic respiration of glucose is summarized as:

A) C₆H₁₂O₆ + 6 O₂ + 6 H₂O $\rightarrow$ 6 CO₂ + 12 H₂O + Energy.
B) C₄H₁₂O₄ + 12 H₂O + 6 CO₂ $\rightarrow$ 6 O₂ + ATP + Energy.
C) C₄H₁₂O₄ + 6 O₂ + 6 H₂O $\rightarrow$ 6 CO₂ + ATP + Energy.
D) C₄H₁₂O₂ + 6 O₂ + ATP $\rightarrow$ 6 CO₂ + 12 H₂O + Energy.
E) C₆H₁₂O₆ + 6 H₂O $\rightarrow$ 6 CO₂ + 12 H₂ + Energy.

Question 8

Aerobic respiration, anaerobic respiration, and fermentation:

A) are endergonic pathways.
B) release free energy.
C) require oxygen.
D) are also known as organismic respiration.
E) are anabolic pathways.

Question 9

The splitting of molecules into smaller components is referred to as:

A) anabolism.
B) metabolism.
C) catabolism.
D) redox.
E) photosynthesis.

Question 10

In eukaryotes, glycolysis occurs in the:

A) mitochondrial inner membrane.
B) lysosomes.
C) Golgi complex.
D) cytosol.
E) mitochondrial matrix.

Question 11

NADH and FADH₂ are the products of:

A) decarboxylation reactions.
B) oxidation-reduction reactions.
C) glycolysis.
D) formation of acetyl coenzyme A.
E) chemiosmosis.

Question 12

Which of the following statements concerning anabolic reactions is FALSE?

A) They are generally endergonic.
B) They usually require ATP.
C) They are part of metabolism.
D) They may produce polysaccharides from monosaccharides.
E) They may split complex molecules into their components.

Question 13

Select the anaerobic pathway.

A) aerobic respiration
B) citric acid cycle
C) electron transport chain
D) fermentation
E) chemiosmosis

Question 14

In aerobic respiration, glucose is completely:

A) reduced to ATP.
B) reduced to energy.
C) oxidized to water.
D) oxidized to carbon dioxide.
E) oxidized and reduced simultaneously.

Question 15

Which of the following statements concerning decarboxylation reactions is FALSE?

A) They occur as part of the citric acid cycle.
B) They produce CO₂ that is then exhaled via breathing.
C) They involve the removal of a carboxyl group (-COOH) from a substrate.
D) They are one type of general reaction that occurs during aerobic respiration.
E) They involve the removal of two protons and two electrons.

Question 16

In glycolysis, glucose receives two phosphate groups from __________, thus forming fructose-1, 6-bisphosphate.

A) ADP
B) ATP
C) a bisphosphate group
D) fructose-1, 6-bisphosphate
E) G3P

Question 17

In aerobic respiration, the electrons associated with the hydrogen atoms in glucose are ultimately transferred to:

A) carbon in a series of steps.
B) oxygen in a series of steps.
C) NADH in a series of steps.
D) the mitochondrial membranes.
E) hydrogen ions.

Question 18

If conditions are aerobic, pyruvate flows directly into the __________ where some of its atoms are converted next to __________.

A) cytosol; oxaloacetate
B) cytosol; ATP
C) mitochondria; glucose-6-phosphate
D) mitochondia; acetyl coenzyme A
E) mitochondria; citrate

Question 19

Which process does not match the location in a typical eukaryotic cell?

A) glycolysis-mitochondrion
B) formation of acetyl coenzyme A-mitochondrion
C) citric acid cycle-mitochondrion
D) electron transport-mitochondrion
E) chemiosmosis-mitochondrion

Question 20

Which of the following is not one of the four stages of the aerobic respiration of glucose?

A) glycolysis
B) formation of acetyl CoA
C) hydrolysis
D) citric acid cycle
E) electron transport

Question 21

During aerobic respiration, oxygen is:

A) formed.
B) reduced.
C) oxidized.
D) catabolized.
E) decarboxylated.

Question 22

In the citric acid cycle, two acetyl CoA molecules are metabolized to:

A) 2 CO₂ + 2 ATPs + 2 NADH + 2 FADH.
B) 4 CO₂ + 6 NADH + 2 FADH₂ + 2 ATP.
C) fructose-1, 6-bisphosphate.
D) glucose + 2 CO₂ + 2 NADH + 2 FADH₂ + 2 ATPs.
E) 2 G3P.

Question 23

Glycolysis yields a net energy profit of __________ ATP molecules per molecule of glucose.

A) 0
B) 1
C) 2
D) 4
E) 6

Question 24

The chemical reaction illustrated in the figure is:

A) the first step in the citric acid cycle.
B) the energy investing phase of glycolysis.
C) fermentation.
D) part of the electron transport chain.
E) the energy capture phase of glycolysis.

Question 25

A drowning death would be most directly due to:

A) The unavailability of glucose to feed into glycolysis.
B) The accumulation of lactate in the muscle tissue due to anaerobic respiration.
C) The breakdown of pyruvate into ethyl alcohol.
D) The lack of oxygen to accept hydrogen.
E) There is not sufficient information to determine which answer is correct.

Question 26

An example of a substrate-level phosphorylation that occurs during glycolysis is the transfer of a phosphate group from a phosphorylated intermediate to:

A) ATP.
B) ADP.
C) NADH.
D) 1,3-bisphosphoglycerate.
E) glucose.

Question 27

Organismal body heat is a:

A) byproduct of endergonic reactions.
B) product of glucose synthesis.
C) byproduct of exergonic reactions.
D) product of anabolism.
E) product of ATP synthesis.

Question 28

A glucose molecule that is metabolized via aerobic respiration has been completely broken down and released as CO₂ by the end of:

A) fermentation.
B) the electron transport chain.
C) glycolysis.
D) ATP synthesis in the mitochondria.
E) the citric acid cycle.

Question 29

Oxidative decarboxylation of two pyruvates yields:

A) 2 glucose molecules.
B) 2 ATP + 4 CO₂ + 2 NADH.
C) 2 G3P.
D) 2 acetyl CoA + 2 CO₂ + 2 NADH.
E) 1 fructose-1, 6-bisphosphate.

Question 30

During the citric acid cycle, each acetyl group entering the cycle yields:

A) 1 ATP, 2 NADH, and 3 FADH₂.
B) 1 ATP, 3 NADH, and 1 FADH₂.
C) 3 ATP, 2 NADH, and 1 FADH₂.
D) 4 ATP, 2 NADH, and 1 FADH₂.
E) 1 ATP, 2 NADH, and 4 FADH₂.

Question 31

The role of the oxygen molecules required for aerobic respiration is:

A) to accept the low energy electrons at the end of the electron transport chain.
B) to form ATP.
C) to produce CO₂.
D) to store high energy electrons to pass to complex I of the electron transport chain.
E) to accept electrons directly from either NADH or FADH₂.

Question 32

In the electron transport chain, exergonic redox processes drive the endergonic reaction in which:

A) ADP is produced by dephosphorylation of ATP.
B) glucose is produced from phosphorylation of ADP.
C) G3P is produced from phosphorylation of ADP.
D) ATP is produced by phosphorylation of ADP.
E) pyruvate is converted to acetyl CoA.

Question 33

In glycolysis, a six-carbon glucose molecule is converted to two three-carbon molecules of:

A) pyruvate.
B) acetate.
C) coenzyme A.
D) oxaloacetate.
E) citrate.

Question 34

Considering only glycolysis and the conversion of pyruvate molecules to acetyl CoA molecules, how many NADH molecules will be produced from one glucose molecule?

A) one
B) two
C) three
D) four
E) five

Question 35

Which of the following steps in the Kreb's cycle directly produces a molecule of ATP (or GTP)?

A) citrate $\rightarrow$ isocitrate
B) isocitrate $\rightarrow$$\alpha$ -ketoglutarate
C) succinyl CoA $\rightarrow$ succinate
D) succinate $\rightarrow$ fumarate
E) malate $\rightarrow$ oxaloacetate

Question 36

In glycolysis, fructose-1, 6-bisphosphate splits, forming two molecules of:

A) ADP.
B) citric acid.
C) G3P.
D) glucose.
E) acetyl CoA.

Question 37

Coenzyme Q:

A) transfers electrons.
B) oxidizes glucose.
C) is the ultimate source of energy in the citric acid cycle.
D) transfers phosphate to ATP.
E) reduces glucose.

Question 38

Peter Mitchell demonstrated ATP production by aerobic bacteria by placing the bacteria in:

A) an acidic environment.
B) a basic environment.
C) an aqueous environment.
D) a buffered environment.
E) a nonpolar environment.

Question 39

One product of the initial (first) reaction of the citric acid cycle is:

A) ATP.
B) NADH.
C) citrate.
D) oxaloacetate.
E) acetyl-CoA.

Question 40

NADH is formed when NAD⁺ accepts:

A) a proton.
B) a hydrogen atom.
C) a pair of protons and an electron.
D) a proton and a pair of electrons.
E) two hydrogen atoms.

Question 41

In chemiosmosis, ATP is produced as hydrogen ions (protons) pass through:

A) the outer mitochondrial membrane.
B) ATP synthase.
C) ATP dehydrogenase.
D) ATP decarboxylase.
E) a series of electron carriers.

Question 42

One gram of __________ contains more than twice the amount of energy of a gram of glucose.

A) amino acids
B) lipids
C) ATP
D) protein
E) starch

Question 43

If yeasts are grown under anaerobic conditions, pyruvate is converted first to __________ and then to __________.

A) citrate; oxaloacetate
B) acetyl coenzyme A; citrate
C) lactate; carbon dioxide
D) acetaldehyde; ethyl alcohol
E) acetaldehyde; lactate

Question 44

Deamination of amino acids in mammals yields amino groups that are converted to __________, which is(are) excreted, and __________, which is(are) converted to one of the reactants of glycolysis or the citric acid cycle.

A) urea; carbon chains
B) amino acids; ATP
C) amino groups; ADP
D) carbon chains; amino acids
E) amines; ATP

Question 45

During fermentation, the immediate fate of the electrons in NADH is that they:

A) are transferred to the electron transport chain.
B) are transferred to an organic molecule.
C) are transferred to O₂.
D) are used to make CO₂.
E) are used to form H₂O.

Question 46

When one molecule of glucose is completely oxidized in aerobic respiration, the net amount of ATP produced is:

A) 2
B) 4
C) 22
D) 34 to 36
E) 36 to 38.

Question 47

Which of the following molecules can be used as a substrate for cellular respiration?

A) glucose only
B) glucose and lipids only
C) glucose and proteins only
D) glucose, lipids and proteins only
E) glucose, lipids, proteins and fatty acids

Question 48

One important regulation point in the aerobic respiration of mammals occurs in glycolysis at the site of the enzyme phosphofructokinase, which is:

A) inhibited by high levels of ATP.
B) inhibited by low levels of ATP.
C) inhibited by high levels of AMP.
D) activated by the presence of O₂.
E) activated by the introduction of glucose.

Question 49

Select the molecule that contains the least stored chemical energy:

A) ethyl alcohol.
B) pyruvate.
C) glucose.
D) lactate.
E) oxygen.

Question 50

Identify and briefly describe the process(es) of cellular respiration that occur in the mitochondria.Indicate the amount of ATP, NADH, and FADH₂ produced in each process.

Question 51

Which of the following statements is not correct about lactic acid fermentation?

A) It is inefficient compared to aerobic respiration.
B) It uses glucose as a substrate.
C) It produces two ATP molecules for every glucose molecule.
D) Oxygen is the final electron acceptor of this pathway.
E) Glycolysis is the only energy-yielding step of this pathway.

Question 52

In the skeletal muscle cells of vertebrates, as many as __________ molecules of ATP are produced from one molecule of glucose.This is less than might be expected, because electrons from NADH produced during glycolysis must be shuttled through the __________ mitochondrial membrane at a cost.

A) 2; outer
B) 2; inner
C) 38; inner
D) 6; outer
E) 36; inner

Question 53

Saturated fatty acids store more energy than unsaturated fatty acids.Based on your knowledge of aerobic respiration, you draw this conclusion because saturated fatty acids:

A) are more highly reduced.
B) are deaminated.
C) lack phosphate.
D) contain more ester linkages.
E) contain more ATP.

Question 54

When hydrogen ions (protons) are pumped across the inner mitochondrial membrane, they form a proton gradient.ATP is then formed by a process known as:

A) glycolysis.
B) the citric acid cycle.
C) chemiosmosis.
D) pyruvate synthesis.
E) substrate-level phosphorylation.

Question 55

The ability of some bacteria to produce lactate is exploited by humans to make:

A) cheese and ethyl alcohol.
B) insulin and antibodies.
C) yogurt and sauerkraut.
D) ethyl alcohol and carbonic acid.
E) carbon dioxide and water.

Question 56

Anaerobic respiration differs from aerobic respiration in that anaerobic respiration:

A) can utilize NO₃ ^- as the terminal electron acceptor.
B) can utilize O₂ as the terminal electron acceptor.
C) produces CO₂.
D) produces ATP.
E) involves an electron transport chain.

Question 57

Which of the following statements about the electron transport chain is true?

A) Protons are pumped out of the mitochondria by the complexes of the electron transport chain.
B) The proton gradient established during electron transport is a form of potential energy.
C) The electron transport chain can be found in the mitochondria of aerobic bacteria and other cells.
D) The movement of protons down a concentration gradient is an endergonic process.
E) ATP synthesis associated with the electron transport chain is an example of substrate level phosphorylation.

Question 58

The production of alcohol or lactate from pyruvate during __________ occurs as a means of regenerating __________ from __________.

A) aerobic respiration; NAD⁺; NADH
B) fermentation; NAD⁺; NADH
C) fermentation; NADH; NAD⁺
D) fermentation; ADP; ATP
E) aerobic respiration; ATP; ADP

Question 59

Select the molecule that contains the most stored chemical energy:

A) ethyl alcohol.
B) water.
C) carbon dioxide.
D) lactate.
E) oxygen.

Question 60

Select the processes that are matched with the incorrect amount of ATP produced by that process per glucose molecule.

A) glycolysis-2 ATP (net)
B) citric acid cycle-4 ATP
C) electron transport chain-32 ATP
D) alcohol fermentation-2 ATP
E) lactate fermentation-2 ATP

Question 61

For each acetyl CoA molecule that enters the citric acid cycle, two CO₂ molecules are produced.
__________________

Question 62

In liver cells, each NADH produced via glycolysis results in two ATP molecules in the electron transport chain.
__________________

Question 63

MATCHING
Match the stage of cellular respiration with the correct process.
a.citric acid cycle
c.electron transport and chemiosmosis
b.glycolysis
d.formation of acetyl CoA
This is the first process that occurs in the mitochondrion.

Question 64

An example of an anabolic reaction is the splitting of a polysaccharide into monosaccharides.
__________________

Question 65

MATCHING
Match the stage of cellular respiration with the correct process.
a.citric acid cycle
c.electron transport and chemiosmosis
b.glycolysis
d.formation of acetyl CoA
GDP is phosphorylated

Question 66

Phosphofructokinase is stimulated by high levels of ATP.
__________________

Question 67

MATCHING
Match the stage of cellular respiration with the correct process.
a.citric acid cycle
c.electron transport and chemiosmosis
b.glycolysis
d.formation of acetyl CoA
ATP synthase is a component.

Question 68

The reactions of the citric acid cycle take place in the matrix of the mitochondrion.
__________________

Question 69

Compare and contrast aerobic and anaerobic pathways used by cells to extract energy from organic molecules.Include the mechanism of ATP formation, the final electron acceptor, and the end products in your comparison.

Question 70

The downhill flow of protons through the ATP synthase complex powers the production of ATP.
__________________

Question 71

In the tricarboxylic acid cycle, oxaloacetate reacts with acetyl CoA forming citrate.
__________________

Question 72

The stage of cellular respiration in which most of the ATP is produced is the citric acid cycle.
__________________

Question 73

For each glucose molecule that begins cellular respiration, the citric acid cycle must turn once.
__________________

Question 74

In the process of aerobic respiration, nitrate can function as the terminal electron acceptor in the electron transport chain.
__________________

Question 75

MATCHING
Match the stage of cellular respiration with the correct process.
a.citric acid cycle
c.electron transport and chemiosmosis
b.glycolysis
d.formation of acetyl CoA
NADH is oxidized.

Question 76

What is chemiosmosis, and how is it used to synthesize ATP? Use the following terms in your explanation: inner mitochondria membrane, mitochondrial matrix, endergonic, exergonic, ADP, P_i, and NADH/FADH₂.

Question 77

If yeast cells are incubated under anaerobic conditions, the pyruvate they produce is converted to lactate.
__________________

Question 78

MATCHING
Match the stage of cellular respiration with the correct process.
a.citric acid cycle
c.electron transport and chemiosmosis
b.glycolysis
d.formation of acetyl CoA
Pyruvate is an endproduct.

Question 79

Substrate level phosphorylation reactions occur in the process of chemiosmosis.
__________________

Question 80

MATCHING
Match the stage of cellular respiration with the correct process.
a.citric acid cycle
c.electron transport and chemiosmosis
b.glycolysis
d.formation of acetyl CoA
Oxaloacetate reacts with an acetyl group.