Question 1

Which electron carrier(s) function in the citric acid cycle?

Accepted Answer

A)  NAD⁺ only 
B)  NADH and FADH₂ 
C)  the electron transport chain 
D)  ADP and ATP 
A)  NAD⁺ only 
B)  NADH and FADH₂ 
C)  the electron transport chain 
D)  ADP and ATP

Question 2

Which of the following processes is driven by chemiosmosis?

Accepted Answer

A)  substrate-level phosphorylation 
B)  oxidative phosphorylation 
C)  ATP hydrolysis 
D)  reduction of NAD⁺ to NADH 
A)  substrate-level phosphorylation 
B)  oxidative phosphorylation 
C)  ATP hydrolysis 
D)  reduction of NAD⁺ to NADH

Question 3

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 4

Where are the proteins of the electron transport chain located?

Accepted Answer

A)  mitochondrial outer membrane 
B)  mitochondrial inner membrane 
C)  mitochondrial intermembrane space 
D)  mitochondrial matrix 
A)  mitochondrial outer membrane 
B)  mitochondrial inner membrane 
C)  mitochondrial intermembrane space 
D)  mitochondrial matrix

Question 5

A person on a strict diet and exercise regimen lost 7 kg (about 15 pounds) of body fat in just two weeks. What is the most likely way that the lost fat left the body?

Accepted Answer

A)  It was released as CO₂ and H₂O. 
B)  It was converted to heat and then released. 
C)  It was converted to ATP, which weighs much less than fat. 
D)  It was eliminated from the body as faeces. 
A)  It was released as CO₂ and H₂O. 
B)  It was converted to heat and then released. 
C)  It was converted to ATP, which weighs much less than fat. 
D)  It was eliminated from the body as faeces.

Question 6

Carbon dioxide (CO₂) is released during which of the following stages of cellular respiration?

Accepted Answer

A)  glycolysis and the oxidation of pyruvate to acetyl CoA 
B)  oxidation of pyruvate to acetyl CoA and the citric acid cycle 
C)  oxidative phosphorylation and fermentation 
D)  fermentation and glycolysis 
A)  glycolysis and the oxidation of pyruvate to acetyl CoA 
B)  oxidation of pyruvate to acetyl CoA and the citric acid cycle 
C)  oxidative phosphorylation and fermentation 
D)  fermentation and glycolysis

Question 7

New biosensors, applied like a temporary tattoo to the skin, can alert serious athletes that they are about to "hit the wall" and will find it difficult to continue exercising. These biosensors monitor lactate, a form of lactic acid, released in sweat during strenuous exercise. Which of the statements below is the best explanation of why athletes would need to monitor lactate levels?

Accepted Answer

A)  During aerobic respiration, muscle cells cannot produce enough lactate to fuel muscle cell contractions, and muscles begin to cramp, thus athletic performance suffers. 
B)  During anaerobic respiration, lactate levels increase when muscles cells need more energy; however, muscles cells eventually fatigue, thus athletes should modify their activities to increase aerobic respiration. 
C)  During aerobic respiration, muscles cells produce too much lactate, which causes a rise in the pH of the muscle cells, thus athletes must consume increased amounts of sports drinks, high in electrolytes, to buffer the pH. 
D)  During anaerobic respiration, muscle cells receive too little oxygen and begin to convert lactate to pyruvate (pyruvic acid), thus athletes experience cramping and fatigue. 
A)  During aerobic respiration, muscle cells cannot produce enough lactate to fuel muscle cell contractions, and muscles begin to cramp, thus athletic performance suffers. 
B)  During anaerobic respiration, lactate levels increase when muscles cells need more energy; however, muscles cells eventually fatigue, thus athletes should modify their activities to increase aerobic respiration. 
C)  During aerobic respiration, muscles cells produce too much lactate, which causes a rise in the pH of the muscle cells, thus athletes must consume increased amounts of sports drinks, high in electrolytes, to buffer the pH. 
D)  During anaerobic respiration, muscle cells receive too little oxygen and begin to convert lactate to pyruvate (pyruvic acid), thus athletes experience cramping and fatigue.

Question 8

In which reactions of cellular respiration and fermentation does substrate-level phosphorylation occur?

Accepted Answer

A)  only in glycolysis 
B)  only in the citric acid cycle 
C)  only in the electron transport chain 
D)  in both glycolysis and the citric acid cycle 
A)  only in glycolysis 
B)  only in the citric acid cycle 
C)  only in the electron transport chain 
D)  in both glycolysis and the citric acid cycle

Question 9

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 10

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

Accepted Answer

A)  It is driven by ATP hydrolysis. 
B)  It includes a series of hydrolysis reactions associated with mitochondrial membranes. 
C)  It consists of a series of redox reactions 
D)  It occurs in the cytoplasm of both prokaryotic and eukaryotic cells. 
A)  It is driven by ATP hydrolysis. 
B)  It includes a series of hydrolysis reactions associated with mitochondrial membranes. 
C)  It consists of a series of redox reactions 
D)  It occurs in the cytoplasm of both prokaryotic and eukaryotic cells.

Question 11

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 12

A young dog has never had much energy. He is brought to a veterinarian for help, and she decides to conduct several diagnostic tests. She discovers that the dog's mitochondria can use only fatty acids and amino acids for respiration, and his cells produce more lactate than normal. Of the following, which is the best explanation of the dog's condition?

Accepted Answer

A)  His mitochondria lack the transport protein that moves pyruvate across the outer mitochondrial membrane. 
B)  His cells cannot move NADH from glycolysis into the mitochondria. 
C)  His cells lack the enzyme in glycolysis that forms pyruvate. 
D)  His cells have a defective electron transport chain, so glucose is metabolised to lactate instead of to acetyl CoA. 
A)  His mitochondria lack the transport protein that moves pyruvate across the outer mitochondrial membrane. 
B)  His cells cannot move NADH from glycolysis into the mitochondria. 
C)  His cells lack the enzyme in glycolysis that forms pyruvate. 
D)  His cells have a defective electron transport chain, so glucose is metabolised to lactate instead of to acetyl CoA.

Question 13

Most CO₂ from catabolism is released during

Accepted Answer

A)  glycolysis. 
B)  the citric acid cycle. 
C)  lactate fermentation. 
D)  electron transport. 
A)  glycolysis. 
B)  the citric acid cycle. 
C)  lactate fermentation. 
D)  electron transport.

Question 14

High levels of citric acid inhibit the enzyme phosphofructokinase, a key enzyme in glycolysis. Citric acid binds to the enzyme at a different location from the active site. This is an example of ________.

Accepted Answer

A)  competitive inhibition 
B)  allosteric regulation 
C)  the specificity of enzymes for their substrates 
D)  positive feedback regulation 
A)  competitive inhibition 
B)  allosteric regulation 
C)  the specificity of enzymes for their substrates 
D)  positive feedback regulation

Question 15

The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the

Accepted Answer

A)  oxidation of glucose and other organic compounds. 
B)  flow of electrons down the electron transport chain. 
C)  H⁺ concentration gradient across the membrane holding ATP synthase. 
D)  transfer of phosphate to ADP. 
A)  oxidation of glucose and other organic compounds. 
B)  flow of electrons down the electron transport chain. 
C)  H⁺ concentration gradient across the membrane holding ATP synthase. 
D)  transfer of phosphate to ADP.

Question 16

Yeast cells that have defective mitochondria incapable of respiration will be able to grow by catabolising 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 17

What happens to a glucose molecule when it loses a hydrogen atom as the result of an oxidation-reduction reaction?

Accepted Answer

A)  The glucose molecule is hydrolysed. 
B)  The glucose molecule is an oxidising agent. 
C)  The glucose molecule is oxidised. 
D)  The glucose molecule is reduced. 
A)  The glucose molecule is hydrolysed. 
B)  The glucose molecule is an oxidising agent. 
C)  The glucose molecule is oxidised. 
D)  The glucose molecule is reduced.

Question 18

What happens when electrons are passed from one atom to a more electronegative atom?

Accepted Answer

A)  The more electronegative atom is reduced, and energy is released. 
B)  The more electronegative atom is reduced, and energy is consumed. 
C)  The more electronegative atom is oxidised, and energy is consumed. 
D)  The more electronegative atom is oxidised, and energy is released. 
A)  The more electronegative atom is reduced, and energy is released. 
B)  The more electronegative atom is reduced, and energy is consumed. 
C)  The more electronegative atom is oxidised, and energy is consumed. 
D)  The more electronegative atom is oxidised, and energy is released.

Question 19

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 20

Which of the following statements about NAD⁺ is true?

Accepted Answer

A)  NAD⁺ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle. 
B)  NAD⁺ has more chemical energy than NADH. 
C)  NAD⁺ can donate electrons for use in oxidative phosphorylation. 
D)  In the absence of NAD⁺, glycolysis can still function. 
A)  NAD⁺ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle. 
B)  NAD⁺ has more chemical energy than NADH. 
C)  NAD⁺ can donate electrons for use in oxidative phosphorylation. 
D)  In the absence of NAD⁺, glycolysis can still function.

Exam 9: Cellular Respiration and Fermentation

Which electron carrier(s) function in the citric acid cycle?

Which of the following processes is driven by chemiosmosis?

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

Where are the proteins of the electron transport chain located?

A person on a strict diet and exercise regimen lost 7 kg (about 15 pounds) of body fat in just two weeks. What is the most likely way that the lost fat left the body?

Carbon dioxide (CO₂) is released during which of the following stages of cellular respiration?

In which reactions of cellular respiration and fermentation does substrate-level phosphorylation occur?

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

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

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?

Most CO₂ from catabolism is released during

High levels of citric acid inhibit the enzyme phosphofructokinase, a key enzyme in glycolysis. Citric acid binds to the enzyme at a different location from the active site. This is an example of ________.

The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the

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

What happens to a glucose molecule when it loses a hydrogen atom as the result of an oxidation-reduction reaction?

What happens when electrons are passed from one atom to a more electronegative atom?

What kinds of cells carry out ATP synthesis by chemiosmosis?

Which of the following statements about NAD⁺ is true?

Evolution, the Themes of Biology, and Scientific Inquiry

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

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

Viruses

Dna Tools and Biotechnology

Genomes and Their Evolution

Descent With Modification: a Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonised Land

Plant Diversity Ii: the Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Vascular Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signalling

Nervous Systems

Sensory and Motor Mechanisms

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