Question 1

Refer to the figure below, which shows a series of coupled reactions.   Which terms belong in the numbered boxes?

Accepted Answer

A)  1 = reduction; 2 = reduction; 3 = oxidation; 4 = oxidation 
B)  1 = oxidation; 2 = oxidation; 3 = reduction; 4 = reduction 
C)  1 = reduction; 2 = oxidation; 3 = reduction; 4 = oxidation 
D)  1 = oxidation; 2 = reduction; 3 = oxidation; 4 = reduction 
E)  1 = oxidation; 2 = reduction; 3 = reduction; 4 = oxidation 
A)  1 = reduction; 2 = reduction; 3 = oxidation; 4 = oxidation 
B)  1 = oxidation; 2 = oxidation; 3 = reduction; 4 = reduction 
C)  1 = reduction; 2 = oxidation; 3 = reduction; 4 = oxidation 
D)  1 = oxidation; 2 = reduction; 3 = oxidation; 4 = reduction 
E)  1 = oxidation; 2 = reduction; 3 = reduction; 4 = oxidation

Question 2

Fatty acids must be converted to _______ before they can be used for mitochondrial ATP production.

Accepted Answer

The answer of Fatty acids must be converted to _______...

Question 3

What is the cellular location of glycolysis in eukaryotes?

Accepted Answer

A)  Cell membrane 
B)  Cytosol 
C)  Mitochondria 
D)  Nucleus 
E)  Lysosome 
A)  Cell membrane 
B)  Cytosol 
C)  Mitochondria 
D)  Nucleus 
E)  Lysosome

Question 4

Refer to the table summarizing information collected from acetyl CoA carboxylase, the enzyme that catalyzes the first committed step in the biosynthesis of fatty acids from acetyl CoA.   In these samples, enzyme purified from rat adipose tissue was used.No other cellular components were present when the enzyme in buffer solution was tested as outlined in the table.Based on the results shown, which statement describes how citrate is likely involved in the regulation of acetyl CoA carboxylase?

Accepted Answer

A)  Citrate activates transcription of the gene encoding the enzyme to increase its levels in the cell. 
B)  Citrate is an inhibitor of the enzyme, operating through a negative feedback mechanism. 
C)  Citrate is an allosteric activator of the enzyme, shifting protein conformational change from an inactive to an active form. 
D)  Citrate inhibits a phosphatase that shifts the enzyme from an inactive to an active conformation by removing a phosphate group covalently bound to the enzyme. 
E)  Citrate activates a protein kinase that induces a shift in the protein shape to an active form through covalent modification. 
A)  Citrate activates transcription of the gene encoding the enzyme to increase its levels in the cell. 
B)  Citrate is an inhibitor of the enzyme, operating through a negative feedback mechanism. 
C)  Citrate is an allosteric activator of the enzyme, shifting protein conformational change from an inactive to an active form. 
D)  Citrate inhibits a phosphatase that shifts the enzyme from an inactive to an active conformation by removing a phosphate group covalently bound to the enzyme. 
E)  Citrate activates a protein kinase that induces a shift in the protein shape to an active form through covalent modification.

Question 5

When NADH is the electron donor to the respiratory chain, 2.5 ATP are formed, but when FADH2 is the electron donor, only 1.5 ATP are formed.This difference occurs because

Accepted Answer

A)  complex I accepts electrons from both NADH and FADH2 but donates the electrons to different sites on the complex, which produces a larger proton gradient for NADH. 
B)  complex I accepts electrons from NADH but not FADH2, resulting in an extra step that allows a larger proton gradient to form. 
C)  complex II accepts electrons from both NADH and FADH2 but donates the electrons to different sites on the complex, which produces a larger proton gradient for NADH. 
D)  energy, in the form of heat, is lost when FADH2, but not NADH, is the electron donor, resulting in lower energy yield. 
E)  NADH interacts with ATP synthase more efficiently than FADH2, resulting in more ATP production. 
A)  complex I accepts electrons from both NADH and FADH2 but donates the electrons to different sites on the complex, which produces a larger proton gradient for NADH. 
B)  complex I accepts electrons from NADH but not FADH2, resulting in an extra step that allows a larger proton gradient to form. 
C)  complex II accepts electrons from both NADH and FADH2 but donates the electrons to different sites on the complex, which produces a larger proton gradient for NADH. 
D)  energy, in the form of heat, is lost when FADH2, but not NADH, is the electron donor, resulting in lower energy yield. 
E)  NADH interacts with ATP synthase more efficiently than FADH2, resulting in more ATP production.

Question 6

A microbiologist is characterizing a newly discovered microorganism that requires an anaerobic environment to live and uses either lactic acid or alcoholic fermentation in its energy metabolism.Which would be a way to determine the type of fermentation the microorganism uses?

Accepted Answer

A)  Measure the stoichiometry of ATP formed per glucose molecule catabolized. 
B)  Measure the stoichiometry of NAD+ oxidized per glucose molecule catabolized. 
C)  Analyze whether NAD+ is regenerated in the cytosol after it is reduced during fermentation. 
D)  Analyze whether two molecules of pyruvate are formed for every one molecule of glucose fermented. 
E)  Analyze whether one molecule of carbon dioxide is released for every one molecule of glucose fermented. 
A)  Measure the stoichiometry of ATP formed per glucose molecule catabolized. 
B)  Measure the stoichiometry of NAD+ oxidized per glucose molecule catabolized. 
C)  Analyze whether NAD+ is regenerated in the cytosol after it is reduced during fermentation. 
D)  Analyze whether two molecules of pyruvate are formed for every one molecule of glucose fermented. 
E)  Analyze whether one molecule of carbon dioxide is released for every one molecule of glucose fermented.

Question 7

During the energy-investing portion of glycolysis, the phosphates from ATP molecules are

Accepted Answer

A)  added to carbon atoms to form fructose 1,6-bisphosphate. 
B)  added to carbon atoms to form 1,3-bisphosphoglycerate. 
C)  wasted as an energy investment in glucose. 
D)  used to make pyruvate from glucose. 
E)  used to make lactate from glucose. 
A)  added to carbon atoms to form fructose 1,6-bisphosphate. 
B)  added to carbon atoms to form 1,3-bisphosphoglycerate. 
C)  wasted as an energy investment in glucose. 
D)  used to make pyruvate from glucose. 
E)  used to make lactate from glucose.

Question 8

A species of bacteria was cultured in a test tube containing a uniform distribution of glucose but a varying distribution of oxygen.Oxygen was highest near the top of the tube and very low at the bottom.If this bacterial species is incapable of carrying out fermentation or other anaerobic energy-harvesting pathways, which test tube represents the expected growth pattern of the bacterial culture?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 9

Refer to the figure below.   Which sequence of metabolic paths could a carbon atom take to go from a molecule of glucose to a molecule of DNA?

Accepted Answer

A)  Glycolysis F1F1F1S1F1F1F10 glycerol biosynthesis F1F1F1S1F1F1F10 triglyceride biosynthesis F1F1F1S1F1F1F10 fatty acid biosynthesis F1F1F1S1F1F1F10 citric acid cycle 
B)  Glycolysis F1F1F1S1F1F1F10 amino acid biosynthesis F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 acetyl CoA synthesis F1F1F1S1F1F1F10 nucleic acid biosynthesis 
C)  Glycolysis F1F1F1S1F1F1F10 pyruvate oxidation F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 amino acid biosynthesis F1F1F1S1F1F1F10 purine biosynthesis 
D)  Glycolysis F1F1F1S1F1F1F10 amino acid biosynthesis F1F1F1S1F1F1F10 protein biosynthesis F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 acetyl CoA synthesis 
E)  Glycolysis F1F1F1S1F1F1F10 pyruvate oxidation F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 electron transport F1F1F1S1F1F1F10 ATP synthesis 
A)  Glycolysis F1F1F1S1F1F1F10 glycerol biosynthesis F1F1F1S1F1F1F10 triglyceride biosynthesis F1F1F1S1F1F1F10 fatty acid biosynthesis F1F1F1S1F1F1F10 citric acid cycle 
B)  Glycolysis F1F1F1S1F1F1F10 amino acid biosynthesis F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 acetyl CoA synthesis F1F1F1S1F1F1F10 nucleic acid biosynthesis 
C)  Glycolysis F1F1F1S1F1F1F10 pyruvate oxidation F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 amino acid biosynthesis F1F1F1S1F1F1F10 purine biosynthesis 
D)  Glycolysis F1F1F1S1F1F1F10 amino acid biosynthesis F1F1F1S1F1F1F10 protein biosynthesis F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 acetyl CoA synthesis 
E)  Glycolysis F1F1F1S1F1F1F10 pyruvate oxidation F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10 electron transport F1F1F1S1F1F1F10 ATP synthesis

Question 10

Energy production occurs in different locations in prokaryotic and eukaryotic cells.Which statement is true for eukaryotes?

Accepted Answer

A)  The conversion of glucose to pyruvate occurs in the mitochondria. 
B)  The conversion of pyruvate to lactate occurs in the mitochondria. 
C)  The conversion of pyruvate to CO2 and H2O occurs in the mitochondria. 
D)  The respiratory chain enzymes are found at the plasma membrane. 
E)  The citric acid cycle enzymes are found in the cytoplasm. 
A)  The conversion of glucose to pyruvate occurs in the mitochondria. 
B)  The conversion of pyruvate to lactate occurs in the mitochondria. 
C)  The conversion of pyruvate to CO2 and H2O occurs in the mitochondria. 
D)  The respiratory chain enzymes are found at the plasma membrane. 
E)  The citric acid cycle enzymes are found in the cytoplasm.

Question 11

_______ is the reduced form of one of the most common electron carriers in cells.

Accepted Answer

The answer of _______ is the reduced form of one...

Question 12

Refer to the figure, showing allosteric regulation of glycolysis and the citric acid cycle.   If a cell is fed a large supply of fatty acids, which outcome can be expected?

Accepted Answer

A)  Glycolysis and pyruvate oxidation will be stimulated, causing citrate to build up and activate fatty acid synthase. 
B)  Oxidation of fatty acids through the citric acid cycle will be stimulated until ATP builds up and inhibits citrate synthase, diverting fatty acids into storage molecules such as triglycerides. 
C)  Glycolysis will be stimulated and pyruvate oxidation will be inhibited as acetyl CoA builds up to high levels in the cell. 
D)  The excess fatty acids will deplete the oxygen supply, causing everything except glycolysis to shut down and activating the lactic acid fermentation pathway. 
E)  Oxidation of fatty acids to form acetyl CoA will be stimulated, which will stimulate gluconeogenesis to form glucose that the cell can store as an energy resource. 
A)  Glycolysis and pyruvate oxidation will be stimulated, causing citrate to build up and activate fatty acid synthase. 
B)  Oxidation of fatty acids through the citric acid cycle will be stimulated until ATP builds up and inhibits citrate synthase, diverting fatty acids into storage molecules such as triglycerides. 
C)  Glycolysis will be stimulated and pyruvate oxidation will be inhibited as acetyl CoA builds up to high levels in the cell. 
D)  The excess fatty acids will deplete the oxygen supply, causing everything except glycolysis to shut down and activating the lactic acid fermentation pathway. 
E)  Oxidation of fatty acids to form acetyl CoA will be stimulated, which will stimulate gluconeogenesis to form glucose that the cell can store as an energy resource.

Question 13

Workers in wine production facilities have an occupational hazard that workers in yogurt-manufacturing facilities do not have.Both wine production and yogurt production involve fermentation.However, only wineries must be diligent about providing proper ventilation to areas where fermentation occurs.This is because wine is made using alcoholic fermentation, which produces _______, a substance that can cause asphyxia, unconsciousness, and even death if present in high levels.Yogurt, made using lactic acid fermentation, does not produce this product.

Accepted Answer

The answer of Workers in wine production facilities have an...

Question 14

Which compounds link glycolysis and the citric acid cycle to the electron transport chain?

Accepted Answer

A)  NADH and ATP 
B)  ADP and Pi 
C)  FADH2 and NADH 
D)  ATP and CO2 
E)  Pyruvate and acetyl CoA 
A)  NADH and ATP 
B)  ADP and Pi 
C)  FADH2 and NADH 
D)  ATP and CO2 
E)  Pyruvate and acetyl CoA

Question 15

Refer to the figure below.   Does this figure have any inaccuracies?

Accepted Answer

A)  No, the figure is accurate as shown. 
B)  Yes, the electrons are shown moving up as they pass along the respiratory chain but they should be shown moving down along the chain. 
C)  Yes, the arrows showing movement of protons from the matrix into the inner membrane are all pointing in the wrong direction and should be reversed. 
D)  Yes, the position of ATP synthase relative to the inner membrane is incorrect and should be reversed so that ATP is shown being synthesized in the intermembrane space. 
E)  Yes, the arrow showing movement of protons through ATP synthase is pointing in the wrong direction; it should be reversed. 
A)  No, the figure is accurate as shown. 
B)  Yes, the electrons are shown moving up as they pass along the respiratory chain but they should be shown moving down along the chain. 
C)  Yes, the arrows showing movement of protons from the matrix into the inner membrane are all pointing in the wrong direction and should be reversed. 
D)  Yes, the position of ATP synthase relative to the inner membrane is incorrect and should be reversed so that ATP is shown being synthesized in the intermembrane space. 
E)  Yes, the arrow showing movement of protons through ATP synthase is pointing in the wrong direction; it should be reversed.

Question 16

The end result of glycolysis includes the formation of many molecules, including the

Accepted Answer

A)  formation of 38 molecules of ATP. 
B)  reduction of 8 molecules of NAD+ to NADH. 
C)  formation of 2 molecules of pyruvate. 
D)  conversion of 1 molecule of glucose to lactic acid. 
E)  production of carbon dioxide. 
A)  formation of 38 molecules of ATP. 
B)  reduction of 8 molecules of NAD+ to NADH. 
C)  formation of 2 molecules of pyruvate. 
D)  conversion of 1 molecule of glucose to lactic acid. 
E)  production of carbon dioxide.

Question 17

The oxidation of acetyl CoA to CO2 occurs via

Accepted Answer

A)  fermentation. 
B)  the citric acid cycle. 
C)  glycolysis. 
D)  oxidative phosphorylation. 
E)  the respiratory chain. 
A)  fermentation. 
B)  the citric acid cycle. 
C)  glycolysis. 
D)  oxidative phosphorylation. 
E)  the respiratory chain.

Question 18

Which path could a carbon atom follow if it began in an amino acid in a protein in some tuna that was eaten by a cat and eventually ended up in a lipid in the cell membrane of one of the cat's muscle cells?

Accepted Answer

A)  Amino acid F1F1F1S1F1F1F10F1F1F1S1F1F1F10citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10acetyl CoA F1F1F1S1F1F1F10F1F1F1S1F1F1F10fatty acid F1F1F1S1F1F1F10F1F1F1S1F1F1F10triglyceride F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
B)  Amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10pyruvate oxidation F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
C)  Amino acid F1F1F1S1F1F1F10F1F1F1S1F1F1F10pyruvate oxidation F1F1F1S1F1F1F10F1F1F1S1F1F1F10gluconeogenesis F1F1F1S1F1F1F10F1F1F1S1F1F1F10glucose F1F1F1S1F1F1F10F1F1F1S1F1F1F10glycerol F1F1F1S1F1F1F10F1F1F1S1F1F1F10triglyceride F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
D)  Amino acid F1F1F1S1F1F1F10 electron transport F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10acetyl CoA F1F1F1S1F1F1F10F1F1F1S1F1F1F10lipid F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
E)  Amino acid F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10acetyl CoA F1F1F1S1F1F1F10F1F1F1S1F1F1F10pyruvate F1F1F1S1F1F1F10F1F1F1S1F1F1F10glycolysis F1F1F1S1F1F1F10F1F1F1S1F1F1F10glycerol F1F1F1S1F1F1F10 triglyceride F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
A)  Amino acid F1F1F1S1F1F1F10F1F1F1S1F1F1F10citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10acetyl CoA F1F1F1S1F1F1F10F1F1F1S1F1F1F10fatty acid F1F1F1S1F1F1F10F1F1F1S1F1F1F10triglyceride F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
B)  Amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10pyruvate oxidation F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
C)  Amino acid F1F1F1S1F1F1F10F1F1F1S1F1F1F10pyruvate oxidation F1F1F1S1F1F1F10F1F1F1S1F1F1F10gluconeogenesis F1F1F1S1F1F1F10F1F1F1S1F1F1F10glucose F1F1F1S1F1F1F10F1F1F1S1F1F1F10glycerol F1F1F1S1F1F1F10F1F1F1S1F1F1F10triglyceride F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
D)  Amino acid F1F1F1S1F1F1F10 electron transport F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10acetyl CoA F1F1F1S1F1F1F10F1F1F1S1F1F1F10lipid F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane 
E)  Amino acid F1F1F1S1F1F1F10 citric acid cycle F1F1F1S1F1F1F10F1F1F1S1F1F1F10acetyl CoA F1F1F1S1F1F1F10F1F1F1S1F1F1F10pyruvate F1F1F1S1F1F1F10F1F1F1S1F1F1F10glycolysis F1F1F1S1F1F1F10F1F1F1S1F1F1F10glycerol F1F1F1S1F1F1F10 triglyceride F1F1F1S1F1F1F10F1F1F1S1F1F1F10cell membrane

Question 19

Carbon-13 is a non-radioactive isotope of carbon that is safe for humans to ingest.This isotope can be identified and quantified using an analytical instrument called a mass spectrometer.The figure below shows results of such an analysis of the fate of 13C-labeled alanine given orally to human volunteers just before they began intensive and prolonged exercise.   From the results shown, it can be concluded that the majority of alanine ingested just before exercise is used as a(n) _______ source.

Accepted Answer

Question 20

Which molecule from glycolysis or the citric acid pathway serves as the building block for lipid synthesis?

Accepted Answer

A)  F1F1F1S1F1F1F10-Ketoglutarate 
B)  Oxaloacetate 
C)  Acetyl CoA 
D)  Pyruvate 
E)  Glucose 
A)  F1F1F1S1F1F1F10-Ketoglutarate 
B)  Oxaloacetate 
C)  Acetyl CoA 
D)  Pyruvate 
E)  Glucose

Exam 9: Pathways That Harvest Chemical Energy

Refer to the figure below, which shows a series of coupled reactions. Which terms belong in the numbered boxes?

Fatty acids must be converted to _______ before they can be used for mitochondrial ATP production.

What is the cellular location of glycolysis in eukaryotes?

When NADH is the electron donor to the respiratory chain, 2.5 ATP are formed, but when FADH2 is the electron donor, only 1.5 ATP are formed.This difference occurs because

A microbiologist is characterizing a newly discovered microorganism that requires an anaerobic environment to live and uses either lactic acid or alcoholic fermentation in its energy metabolism.Which would be a way to determine the type of fermentation the microorganism uses?

During the energy-investing portion of glycolysis, the phosphates from ATP molecules are

Refer to the figure below. Which sequence of metabolic paths could a carbon atom take to go from a molecule of glucose to a molecule of DNA?

Energy production occurs in different locations in prokaryotic and eukaryotic cells.Which statement is true for eukaryotes?

_______ is the reduced form of one of the most common electron carriers in cells.

Refer to the figure, showing allosteric regulation of glycolysis and the citric acid cycle. If a cell is fed a large supply of fatty acids, which outcome can be expected?

Which compounds link glycolysis and the citric acid cycle to the electron transport chain?

Refer to the figure below. Does this figure have any inaccuracies?

The end result of glycolysis includes the formation of many molecules, including the

The oxidation of acetyl CoA to CO2 occurs via

Which path could a carbon atom follow if it began in an amino acid in a protein in some tuna that was eaten by a cat and eventually ended up in a lipid in the cell membrane of one of the cat's muscle cells?

Which molecule from glycolysis or the citric acid pathway serves as the building block for lipid synthesis?

Studying Life

Small Molecules and the Chemistry of Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Communication and Multicellularity

Energy, Enzymes, and Metabolism

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

Populations

Species Interactions

Communities

Ecosystems

A Changing Biosphere

Filters

When NADH is the electron donor to the respiratory chain, 2.5 ATP are formed, but when FADH₂ is the electron donor, only 1.5 ATP are formed.This difference occurs because

The oxidation of acetyl CoA to CO₂ occurs via