Question 1

In chemiosmotic phosphorylation, 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 system 
B) energy released from substrate-level phosphorylation 
C) energy released from movement of protons through ATP synthase, against the electrochemical gradient 
D) energy released from movement of protons through ATP synthase, down the electrochemical gradient 
E) No external source of energy is required because the reaction is exergonic. 
A) energy released as electrons flow through the electron transport system 
B) energy released from substrate-level phosphorylation 
C) energy released from movement of protons through ATP synthase, against the electrochemical gradient 
D) energy released from movement of protons through ATP synthase, down the electrochemical gradient 
E) No external source of energy is required because the reaction is exergonic.

Question 2

During cellular respiration, acetyl CoA accumulates in which location?

Accepted Answer

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

Question 3

Use the following information to answer the questions below.
Exposing inner mitochondrial membranes to ultrasonic vibrations will disrupt the membranes. However, the fragments will reseal "inside out." These little vesicles that result can still transfer electrons from NADH to oxygen and synthesize ATP. If the membranes are agitated further, however, the ability to synthesize ATP is lost.
-These inside-out membrane vesicles

Accepted Answer

A) will become acidic inside the vesicles when NADH is added. 
B) will become alkaline inside the vesicles when NADH is added. 
C) will make ATP from ADP and   ᵢ if transferred to a pH 4 buffered solution after incubation in a pH 7 buffered solution. 
D) will hydrolyze ATP to pump protons out of the interior of the vesicle to the exterior. 
E) will reverse electron flow to generate NADH from NAD⁺ in the absence of oxygen. 
A) will become acidic inside the vesicles when NADH is added. 
B) will become alkaline inside the vesicles when NADH is added. 
C) will make ATP from ADP and   ᵢ if transferred to a pH 4 buffered solution after incubation in a pH 7 buffered solution. 
D) will hydrolyze ATP to pump protons out of the interior of the vesicle to the exterior. 
E) will reverse electron flow to generate NADH from NAD⁺ in the absence of oxygen.

Question 4

Where do the catabolic products of fatty acid breakdown enter into the citric acid cycle?

Accepted Answer

A) pyruvate 
B) malate or fumarate 
C) acetyl CoA 
D) α-ketoglutarate 
E) succinyl CoA 
A) pyruvate 
B) malate or fumarate 
C) acetyl CoA 
D) α-ketoglutarate 
E) succinyl CoA

Question 5

Which co-enzyme is the most versatile electron acceptor in the cell?

Accepted Answer

A) Acetyl Co-A 
B) FAD 
C) NAD⁺ 
D) ATP 
E) CytC 
A) Acetyl Co-A 
B) FAD 
C) NAD⁺ 
D) ATP 
E) CytC

Question 6

Use the following information to answer the questions below.
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.
-These three steps result in the formation of

Accepted Answer

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. 
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.

Question 7

During glycolysis, when each molecule of glucose is catabolized to two molecules of pyruvate, most of the potential energy contained in glucose is

Accepted Answer

A) transferred to ADP, forming ATP. 
B) transferred directly to ATP. 
C) retained in the two pyruvates. 
D) stored in the NADH produced. 
E) used to phosphorylate fructose to form fructose 6-phosphate. 
A) transferred to ADP, forming ATP. 
B) transferred directly to ATP. 
C) retained in the two pyruvates. 
D) stored in the NADH produced. 
E) used to phosphorylate fructose to form fructose 6-phosphate.

Question 8

In a mitochondrion, if the matrix ATP concentration is high, and the intermembrane space proton concentration is too low to generate sufficient proton-motive force, then

Accepted Answer

A) ATP synthase will increase the rate of ATP synthesis. 
B) ATP synthase will stop working. 
C) ATP synthase will hydrolyze ATP and pump protons into the intermembrane space. 
D) ATP synthase will hydrolyze ATP and pump protons into the matrix. 
A) ATP synthase will increase the rate of ATP synthesis. 
B) ATP synthase will stop working. 
C) ATP synthase will hydrolyze ATP and pump protons into the intermembrane space. 
D) ATP synthase will hydrolyze ATP and pump protons into the matrix.

Question 9

What carbon sources can yeast cells metabolize to make ATP from ADP under anaerobic conditions?

Accepted Answer

A) glucose 
B) ethanol 
C) pyruvate 
D) lactic acid 
E) either ethanol or lactic acid 
A) glucose 
B) ethanol 
C) pyruvate 
D) lactic acid 
E) either ethanol or lactic acid

Question 10

A molecule that is phosphorylated

Accepted Answer

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 potential energy; it is primed to do cellular work. 
E) has less energy than before its phosphorylation and therefore less energy for cellular work. 
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 potential energy; it is primed to do cellular work. 
E) has less energy than before its phosphorylation and therefore less energy for cellular work.

Question 11

In vertebrate animals, brown fat tissue's colour is due to abundant blood vessels and capillaries. White fat tissue, on the other hand, is specialized for fat storage and contains relatively few blood vessels or capillaries. Brown fat cells have a specialized protein that dissipates the proton-motive force across the mitochondrial membranes. Which of the following might be the function of the brown fat tissue?

Accepted Answer

A) to increase the rate of oxidative phosphorylation from its few mitochondria 
B) to allow the animals to regulate their metabolic rate when it is especially hot 
C) to increase the production of ATP 
D) to allow other membranes of the cell to perform mitochondrial functions 
E) to regulate temperature by converting most of the energy from NADH oxidation to heat 
A) to increase the rate of oxidative phosphorylation from its few mitochondria 
B) to allow the animals to regulate their metabolic rate when it is especially hot 
C) to increase the production of ATP 
D) to allow other membranes of the cell to perform mitochondrial functions 
E) to regulate temperature by converting most of the energy from NADH oxidation to heat

Question 12

Use the following information to answer the questions below.
You have collected samples from mud at the bottom of a nearby pond and have isolated different bacteria and protists from that community. You put the cultures in appropriate media in test tubes with loose-fitting lids and leave for the night, confident that your cultures will be growing well when you return.
-When you come back the next morning, you notice that the culture in test tube A hasn't grown at all, while all the other ones have. You conclude that the culture must be composed of

Accepted Answer

A) obligate aerobes. 
B) obligate anaerobes. 
C) facultative anaerobes. 
D) sulphate-reducing bacteria. 
E) fermenting organisms. 
A) obligate aerobes. 
B) obligate anaerobes. 
C) facultative anaerobes. 
D) sulphate-reducing bacteria. 
E) fermenting organisms.

Question 13

Which of the following statements describes NAD⁺?

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⁺ is oxidized 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. 
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⁺ is oxidized 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.

Question 14

A proton-motive force is the conversion of ________ energy into ________ energy.

Accepted Answer

A) potential; chemical 
B) potential; thermal 
C) chemical; kinetic 
D) chemical; potential 
E) solar; chemical 
A) potential; chemical 
B) potential; thermal 
C) chemical; kinetic 
D) chemical; potential 
E) solar; chemical

Question 15

During aerobic respiration, H₂O is formed. Where does the oxygen atom for the formation of the water come from?

Accepted Answer

A) carbon dioxide (CO₂) 
B) glucose (C₆H₁₂O₆) 
C) molecular oxygen (O₂) 
D) pyruvate (C₃H₃O₃⁻) 
E) lactate (C₃H₅O₃⁻) 
A) carbon dioxide (CO₂) 
B) glucose (C₆H₁₂O₆) 
C) molecular oxygen (O₂) 
D) pyruvate (C₃H₃O₃⁻) 
E) lactate (C₃H₅O₃⁻)

Question 16

In prokaryotes, the respiratory electron transport chain is located

Accepted Answer

A) in the mitochondrial inner membrane. 
B) in the mitochondrial outer membrane. 
C) in the plasma membrane. 
D) in the cytoplasm. 
E) in the bacterial outer membrane. 
A) in the mitochondrial inner membrane. 
B) in the mitochondrial outer membrane. 
C) in the plasma membrane. 
D) in the cytoplasm. 
E) in the bacterial outer membrane.

Question 17

Use the following information to answer the questions below.
A young animal has never had much energy. He is brought to a veterinarian for help and is sent to the animal hospital for some tests. There they discover his mitochondria can use only fatty acids and amino acids for respiration, and his cells produce more lactate than normal.
-What would the veterinarian suggest to help this dog?

Accepted Answer

A) Increase his carbohydrate intake to provide more substrate for glycolysis. 
B) Change his diet, reducing carbohydrates and increasing protein and fats. 
C) Keep him sedentary, not allowing him to exercise much. 
D) Try a different source of carbohydrates in his diet. 
E) Take energy pills. 
A) Increase his carbohydrate intake to provide more substrate for glycolysis. 
B) Change his diet, reducing carbohydrates and increasing protein and fats. 
C) Keep him sedentary, not allowing him to exercise much. 
D) Try a different source of carbohydrates in his diet. 
E) Take energy pills.

Question 18

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

Accepted Answer

A) lactate 
B) glyceraldehydes-3-phosphate 
C) oxaloacetate 
D) acetyl CoA 
E) citrate 
A) lactate 
B) glyceraldehydes-3-phosphate 
C) oxaloacetate 
D) acetyl CoA 
E) citrate

Question 19

Inside an active mitochondrion, most electrons follow which pathway?

Accepted Answer

A) glycolysis → NADH → oxidative phosphorylation → ATP → oxygen 
B) citric acid cycle → FADH₂ → electron transport chain → ATP 
C) electron transport chain → citric acid cycle → ATP → oxygen 
D) pyruvate → citric acid cycle → ATP → NADH → oxygen 
E) citric acid cycle → NADH → electron transport chain → oxygen 
A) glycolysis → NADH → oxidative phosphorylation → ATP → oxygen 
B) citric acid cycle → FADH₂ → electron transport chain → ATP 
C) electron transport chain → citric acid cycle → ATP → oxygen 
D) pyruvate → citric acid cycle → ATP → NADH → oxygen 
E) citric acid cycle → NADH → electron transport chain → oxygen

Question 20

How many oxygen molecules (O)are required each time a molecule of glucose (C₆H₁₂O) is completely oxidized to carbon dioxide and water via aerobic respiration?

Accepted Answer

A) 1 
B) 3 
C) 6 
D) 12 
E) 30 
A) 1 
B) 3 
C) 6 
D) 12 
E) 30

Exam 9: Cellular Respiration and Fermentation

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

During cellular respiration, acetyl CoA accumulates in which location?

Where do the catabolic products of fatty acid breakdown enter into the citric acid cycle?

Which co-enzyme is the most versatile electron acceptor in the cell?

During glycolysis, when each molecule of glucose is catabolized to two molecules of pyruvate, most of the potential energy contained in glucose is

In a mitochondrion, if the matrix ATP concentration is high, and the intermembrane space proton concentration is too low to generate sufficient proton-motive force, then

What carbon sources can yeast cells metabolize to make ATP from ADP under anaerobic conditions?

A molecule that is phosphorylated

Which of the following statements describes NAD⁺?

A proton-motive force is the conversion of ________ energy into ________ energy.

During aerobic respiration, H₂O is formed. Where does the oxygen atom for the formation of the water come from?

In prokaryotes, the respiratory electron transport chain is located

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

Inside an active mitochondrion, most electrons follow which pathway?

How many oxygen molecules (O)are required each time a molecule of glucose (C₆H₁₂O) is completely oxidized to carbon dioxide and water via aerobic respiration?

Introduction: Evolution and Themes of Biology

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

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 Colonized 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

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

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

Filters

A proton-motive force is the conversion of energy into energy.