Question 1

In liver cells, the inner mitochondrial membranes are about five times the area of the outer mitochondrial membranes. What purpose must this serve?

Accepted Answer

A)  It allows for an increased rate of glycolysis. 
B)  It allows for an increased rate of the citric acid cycle. 
C)  It increases the surface for oxidative phosphorylation. 
D)  It increases the surface for substrate-level phosphorylation. 
A)  It allows for an increased rate of glycolysis. 
B)  It allows for an increased rate of the citric acid cycle. 
C)  It increases the surface for oxidative phosphorylation. 
D)  It increases the surface for substrate-level phosphorylation.

Question 2

Yeast cells that have defective mitochondria incapable of respiration will be able to grow by catabolizing which of the following carbon sources for energy?

Accepted Answer

A)  glucose 
B)  cholesterol 
C)  fatty acids 
D)  amino acids 
A)  glucose 
B)  cholesterol 
C)  fatty acids 
D)  amino acids

Question 3

Which of the following processes generates a proton-motive force in mitochondria?

Accepted Answer

A)  the flow of protons through ATP synthase down their concentration gradient 
B)  the reduction of NAD⁺ by the first electron carrier in the electron transport chain 
C)  lowering of pH in the mitochondrial matrix 
D)  pumping of hydrogen ions from the mitochondrial matrix across the inner membrane and into the intermembrane space 
A)  the flow of protons through ATP synthase down their concentration gradient 
B)  the reduction of NAD⁺ by the first electron carrier in the electron transport chain 
C)  lowering of pH in the mitochondrial matrix 
D)  pumping of hydrogen ions from the mitochondrial matrix across the inner membrane and into the intermembrane space

Question 4

Starting with one molecule of glucose, glycolysis results in the net production of which of the following sets of energy-containing products?

Accepted Answer

A)  2 NAD⁺, 2 pyruvate, and 2 ATP 
B)  2 NADH, 2 pyruvate, and 2 ATP 
C)  4 NADH, 2 pyruvate, and 4 ATP 
D)  6 CO₂, 2 pyruvate, and 2 ATP 
A)  2 NAD⁺, 2 pyruvate, and 2 ATP 
B)  2 NADH, 2 pyruvate, and 2 ATP 
C)  4 NADH, 2 pyruvate, and 4 ATP 
D)  6 CO₂, 2 pyruvate, and 2 ATP

Question 5

Fatty acids usually have an even number of carbons in their structures. Catabolism of fatty acids produces two-carbon fragments that are converted to acetyl CoA molecules. What is the most likely way in which these acetyl CoA molecules would be metabolized in aerobic cellular respiration?

Accepted Answer

A)  They would directly enter the electron transport chain. 
B)  They would directly enter the energy-yielding phase of glycolysis. 
C)  They would be converted to pyruvate and then undergo pyruvate oxidation upon transport into mitochondria. 
D)  They would directly enter the citric acid cycle. 
A)  They would directly enter the electron transport chain. 
B)  They would directly enter the energy-yielding phase of glycolysis. 
C)  They would be converted to pyruvate and then undergo pyruvate oxidation upon transport into mitochondria. 
D)  They would directly enter the citric acid cycle.

Question 6

In chemiosmosis, what is the most direct source of energy that is used to convert ADP +   ᵢ to ATP?

Accepted Answer

A)  energy released as electrons flow through the electron transport chain 
B)  energy released from substrate-level phosphorylation 
C)  energy released from movement of protons through ATP synthase, down their electrochemical gradient 
D)  energy released as electrons are transported across the inner mitochondrial membrane 
A)  energy released as electrons flow through the electron transport chain 
B)  energy released from substrate-level phosphorylation 
C)  energy released from movement of protons through ATP synthase, down their electrochemical gradient 
D)  energy released as electrons are transported across the inner mitochondrial membrane

Question 7

Following glycolysis and the citric acid cycle, but before the electron transport chain and oxidative phosphorylation, the carbon skeleton of glucose has been broken down to CO₂ with some net gain of ATP. Most of the energy from the original glucose molecule at that point in the process, however, is stored in the form of which of the following molecules?

Accepted Answer

A)  acetyl-CoA 
B)  NAD⁺ 
C)  pyruvate 
D)  NADH 
A)  acetyl-CoA 
B)  NAD⁺ 
C)  pyruvate 
D)  NADH

Question 8

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?

Accepted Answer

A)  the citric acid cycle 
B)  the electron transport chain 
C)  glycolysis 
D)  reduction of pyruvate to lactate 
A)  the citric acid cycle 
B)  the electron transport chain 
C)  glycolysis 
D)  reduction of pyruvate to lactate

Question 9

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

Accepted Answer

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⁺ 
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⁺

Question 10

What kinds of cells carry out ATP synthesis by chemiosmosis?

Accepted Answer

A)  all cells, both prokaryotic and eukaryotic, exclusively using oxygen as the electron acceptor 
B)  only animal cells in mitochondria, exclusively using oxygen as the electron acceptor 
C)  only eukaryotic cells, both plant and animal, using either oxygen or other electron acceptors 
D)  all respiring cells, both prokaryotic and eukaryotic, using either oxygen or other electron acceptors 
A)  all cells, both prokaryotic and eukaryotic, exclusively using oxygen as the electron acceptor 
B)  only animal cells in mitochondria, exclusively using oxygen as the electron acceptor 
C)  only eukaryotic cells, both plant and animal, using either oxygen or other electron acceptors 
D)  all respiring cells, both prokaryotic and eukaryotic, using either oxygen or other electron acceptors

Question 11

The enzyme phosphofructokinase (PFK)catalyzes a key step in glycolysis. About 10% of Springer spaniels suffer from canine PFK deficiency. Given its critical role in glycolysis, which of the following conditions would be a likely consequence for dogs afflicted with this disorder?

Accepted Answer

A)  They would die as embryos. 
B)  They would have elevated blood-glucose levels, which may result in a high incidence of diabetes. 
C)  They would be lethargic and readily tire from exercise. 
D)  They would carry out elevated levels of oxidative phosphorylation. 
A)  They would die as embryos. 
B)  They would have elevated blood-glucose levels, which may result in a high incidence of diabetes. 
C)  They would be lethargic and readily tire from exercise. 
D)  They would carry out elevated levels of oxidative phosphorylation.

Question 12

Which of the following statements describes a primary function of both alcohol fermentation and lactic acid fermentation?

Accepted Answer

A)  reduction of NAD⁺ to NADH 
B)  reduction of FAD to FADH₂ 
C)  oxidation of NADH to NAD⁺ 
D)  hydrolysis of ATP to ADP +   ᵢ 
A)  reduction of NAD⁺ to NADH 
B)  reduction of FAD to FADH₂ 
C)  oxidation of NADH to NAD⁺ 
D)  hydrolysis of ATP to ADP +   ᵢ

Question 13

Water is one of the end products of aerobic respiration. What is the source of the oxygen atom used in formation of the water?

Accepted Answer

A)  carbon dioxide (CO₂) 
B)  glucose (C₆H₁₂O₆) 
C)  molecular oxygen (O₂) 
D)  pyruvate (C₃H₃O₃⁻) 
A)  carbon dioxide (CO₂) 
B)  glucose (C₆H₁₂O₆) 
C)  molecular oxygen (O₂) 
D)  pyruvate (C₃H₃O₃⁻)

Question 14

When a molecule of NAD⁺ (nicotinamide adenine dinucleotide)gains a hydrogen atom (not a proton), the molecule becomes ________.

Accepted Answer

A)  dehydrogenated 
B)  oxidized 
C)  reduced 
D)  redoxed 
A)  dehydrogenated 
B)  oxidized 
C)  reduced 
D)  redoxed

Question 15

What is the oxidizing agent in the following reaction?
Pyruvate + NADH + H⁺ → Lactate + NAD⁺

Accepted Answer

A)  NADH 
B)  NAD⁺ 
C)  lactate 
D)  pyruvate 
A)  NADH 
B)  NAD⁺ 
C)  lactate 
D)  pyruvate

Question 16

During which of the following metabolic processes is most of the CO₂ from the catabolism of glucose is released?

Accepted Answer

A)  glycolysis 
B)  electron transport 
C)  oxidation of pyruvate to acetyl-CoA 
D)  the citric acid cycle 
A)  glycolysis 
B)  electron transport 
C)  oxidation of pyruvate to acetyl-CoA 
D)  the citric acid cycle

Question 17

Use the following information to answer the question below.
 
The citric acid cycle.
If you were to add one of the eight citric acid cycle intermediates to the culture medium of yeast growing in the laboratory, what do you think would happen to the rates of ATP and carbon dioxide production?

Accepted Answer

A)  There would be no change in ATP production, but the rate of carbon dioxide production would increase. 
B)  The rates of ATP production and carbon dioxide production would both increase. 
C)  The rate of ATP production would increase, but the rate of carbon dioxide production would decrease. 
D)  The rates of ATP and carbon dioxide production would both decrease. 
A)  There would be no change in ATP production, but the rate of carbon dioxide production would increase. 
B)  The rates of ATP production and carbon dioxide production would both increase. 
C)  The rate of ATP production would increase, but the rate of carbon dioxide production would decrease. 
D)  The rates of ATP and carbon dioxide production would both decrease.

Question 18

If glucose is the sole energy source, what fraction of the carbon dioxide exhaled by animals is generated only by the reactions involved in oxidation of pyruvate to acetyl CoA?

Accepted Answer

A)  1/6 
B)  1/3 
C)  2/3 
D)  all of it 
A)  1/6 
B)  1/3 
C)  2/3 
D)  all of it

Question 19

Use the following information to answer the question below.
 
The citric acid cycle.
If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle shown in the accompanying figure?

Accepted Answer

A)  Oxaloacetate will decrease and citric acid will accumulate. 
B)  Oxaloacetate will accumulate and citric acid will decrease. 
C)  Both oxaloacetate and citric acid will decrease. 
D)  Both oxaloacetate and citric acid will accumulate. 
A)  Oxaloacetate will decrease and citric acid will accumulate. 
B)  Oxaloacetate will accumulate and citric acid will decrease. 
C)  Both oxaloacetate and citric acid will decrease. 
D)  Both oxaloacetate and citric acid will accumulate.

Question 20

In the absence of oxygen, yeast cells can obtain energy by fermentation, which results in the production of which of the following sets of molecules?

Accepted Answer

A)  ATP, CO₂, and ethanol (ethyl alcohol) 
B)  ATP, CO₂, and lactate 
C)  ATP, NADH, and ethanol 
D)  ATP, CO₂, and acetyl CoA 
A)  ATP, CO₂, and ethanol (ethyl alcohol) 
B)  ATP, CO₂, and lactate 
C)  ATP, NADH, and ethanol 
D)  ATP, CO₂, and acetyl CoA

Exam 9: Cellular Respiration and Fermentation

In liver cells, the inner mitochondrial membranes are about five times the area of the outer mitochondrial membranes. What purpose must this serve?

Yeast cells that have defective mitochondria incapable of respiration will be able to grow by catabolizing which of the following carbon sources for energy?

Which of the following processes generates a proton-motive force in mitochondria?

Starting with one molecule of glucose, glycolysis results in the net production of which of the following sets of energy-containing products?

Fatty acids usually have an even number of carbons in their structures. Catabolism of fatty acids produces two-carbon fragments that are converted to acetyl CoA molecules. What is the most likely way in which these acetyl CoA molecules would be metabolized in aerobic cellular respiration?

In chemiosmosis, what is the most direct source of energy that is used to convert ADP + ᵢ to ATP?

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?

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

What kinds of cells carry out ATP synthesis by chemiosmosis?

The enzyme phosphofructokinase (PFK)catalyzes a key step in glycolysis. About 10% of Springer spaniels suffer from canine PFK deficiency. Given its critical role in glycolysis, which of the following conditions would be a likely consequence for dogs afflicted with this disorder?

Which of the following statements describes a primary function of both alcohol fermentation and lactic acid fermentation?

Water is one of the end products of aerobic respiration. What is the source of the oxygen atom used in formation of the water?

When a molecule of NAD⁺ (nicotinamide adenine dinucleotide)gains a hydrogen atom (not a proton), the molecule becomes ________.

What is the oxidizing agent in the following reaction? Pyruvate + NADH + H⁺ → Lactate + NAD⁺

During which of the following metabolic processes is most of the CO₂ from the catabolism of glucose is released?

Use the following information to answer the question below. The citric acid cycle. If you were to add one of the eight citric acid cycle intermediates to the culture medium of yeast growing in the laboratory, what do you think would happen to the rates of ATP and carbon dioxide production?

If glucose is the sole energy source, what fraction of the carbon dioxide exhaled by animals is generated only by the reactions involved in oxidation of pyruvate to acetyl CoA?

Use the following information to answer the question below. The citric acid cycle. If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle shown in the accompanying figure?

In the absence of oxygen, yeast cells can obtain energy by fermentation, which results in the production of which of the following sets of molecules?

Evolution, the Themes of Biology, and Scientific Inquiry

The Chemical Context of Life

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The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

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Cell Communication

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Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

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Descent with Modification: A Darwinian View of Life

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Basic Principles of Animal Form and Function

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