Question 1

Like glycolysis, fermentation occurs in the

Accepted Answer

A)  mitochondria. 
B)  chloroplasts. 
C)  cytosol. 
D)  mitochondrial matrix. 
E)  inner mitochondrial space. 
A)  mitochondria. 
B)  chloroplasts. 
C)  cytosol. 
D)  mitochondrial matrix. 
E)  inner mitochondrial space.

Question 2

Which statement about metabolic pathways is true?

Accepted Answer

A)  Complex chemical transformations in the cell occur in a single reaction. 
B)  Each reaction of the pathway requires O2. 
C)  In eukaryotes, the pathways exist in the cytoplasm. 
D)  The pathways vary from organism to organism. 
E)  Each pathway is regulated by specific enzymes. 
A)  Complex chemical transformations in the cell occur in a single reaction. 
B)  Each reaction of the pathway requires O2. 
C)  In eukaryotes, the pathways exist in the cytoplasm. 
D)  The pathways vary from organism to organism. 
E)  Each pathway is regulated by specific enzymes.

Question 3

Refer to the figure below, which shows an oxidation-reduction reaction that occurs spontaneously.   Which statement correctly compares the free energy stored in molecules shown in the figure?

Accepted Answer

A)  The reduced form of B has greater free energy than the reduced form of A. 
B)  The oxidized form of B has greater free energy than the reduced form of A. 
C)  The reduced form of A has greater free energy than the oxidized form of A. 
D)  The oxidized form of B has greater free energy than the reduced form of B. 
E)  The oxidized form of A has greater free energy than the reduced form of B. 
A)  The reduced form of B has greater free energy than the reduced form of A. 
B)  The oxidized form of B has greater free energy than the reduced form of A. 
C)  The reduced form of A has greater free energy than the oxidized form of A. 
D)  The oxidized form of B has greater free energy than the reduced form of B. 
E)  The oxidized form of A has greater free energy than the reduced form of B.

Question 4

Which statement best describes steps 1, 2, and 3 of glycolysis (glucose F1F1F1S1F1F1F10 glucose 6-phosphate F1F1F1S1F1F1F10 fructose 1,6-bisphosphate)?

Accepted Answer

A)  A six-carbon molecule is broken down into three two-carbon molecules. 
B)  All three reactions are exergonic. 
C)  These reactions produce energy in the form of one NADH per glucose. 
D)  These reactions require energy in the form of one ATP per glucose. 
E)  These reactions require energy in the form of two ATP per glucose molecule. 
A)  A six-carbon molecule is broken down into three two-carbon molecules. 
B)  All three reactions are exergonic. 
C)  These reactions produce energy in the form of one NADH per glucose. 
D)  These reactions require energy in the form of one ATP per glucose. 
E)  These reactions require energy in the form of two ATP per glucose molecule.

Question 5

Refer to the figure below, showing inputs and outputs of glucose oxidation in a cell under aerobic conditions.   Each box with a question mark should be labeled _______.

Accepted Answer

The answer of Refer to the figure below, showing inputs...

Question 6

Refer to the figure below.   This reaction links glycolysis to the citric acid cycle.Which statement correctly describes the chemical changes depicted in this reaction?

Accepted Answer

A)  Pyruvate is decarboxylated and oxidized to acetyl CoA, and NAD+ is reduced to NADH. 
B)  Pyruvate is reduced to acetyl CoA, and NAD+ is oxidized to NADH. 
C)  Coenzyme A is oxidized to acetyl CoA, and NAD+ is reduced to NADH. 
D)  Coenzyme A is reduced to acetyl CoA, and NAD+ is oxidized to NADH. 
E)  Coenzyme A is oxidized to CO2, and NAD+ is reduced to NADH. 
A)  Pyruvate is decarboxylated and oxidized to acetyl CoA, and NAD+ is reduced to NADH. 
B)  Pyruvate is reduced to acetyl CoA, and NAD+ is oxidized to NADH. 
C)  Coenzyme A is oxidized to acetyl CoA, and NAD+ is reduced to NADH. 
D)  Coenzyme A is reduced to acetyl CoA, and NAD+ is oxidized to NADH. 
E)  Coenzyme A is oxidized to CO2, and NAD+ is reduced to NADH.

Question 7

Under anaerobic conditions, pyruvate

Accepted Answer

A)  is converted to lactate or tricarboxylic acids. 
B)  is fermented to lactate or alcohol. 
C)  enters the citric acid cycle. 
D)  is reduced to lactate. 
E)  is broken down on the cell membrane. 
A)  is converted to lactate or tricarboxylic acids. 
B)  is fermented to lactate or alcohol. 
C)  enters the citric acid cycle. 
D)  is reduced to lactate. 
E)  is broken down on the cell membrane.

Question 8

The main difference between lactic acid fermentation and alcoholic fermentation is that lactic acid fermentation

Accepted Answer

A)  regenerates a three-carbon molecule and alcoholic fermentation does not. 
B)  regenerates NAD+ but alcoholic fermentation does not. 
C)  produces more energy than alcoholic fermentation. 
D)  produces less energy than alcoholic fermentation. 
E)  regenerates a two-carbon molecule, but alcoholic fermentation does not. 
A)  regenerates a three-carbon molecule and alcoholic fermentation does not. 
B)  regenerates NAD+ but alcoholic fermentation does not. 
C)  produces more energy than alcoholic fermentation. 
D)  produces less energy than alcoholic fermentation. 
E)  regenerates a two-carbon molecule, but alcoholic fermentation does not.

Question 9

Refer to the reaction below. Glyceraldehyde 3-phosphate (G3P) + NAD+ + H+ + Pi F1F1F1S1F1F1F10F1F1F1S1F1F1F101,3-bisphosphoglycerate (BPG) + NADH
In this redox reaction, _______ is oxidized and _______ is reduced.

Accepted Answer

A)  G3P; NAD+ 
B)  BPG; NADH + H+ 
C)  G3P; NADH + H+ 
D)  NAD+; NADH + H+ 
E)  NAD+; G3P 
A)  G3P; NAD+ 
B)  BPG; NADH + H+ 
C)  G3P; NADH + H+ 
D)  NAD+; NADH + H+ 
E)  NAD+; G3P

Question 10

The link between glycolysis and the citric acid cycle is called _______.

Accepted Answer

The answer of The link between glycolysis and the citric...

Question 11

How are steps 1-3 of glycolysis different from steps 6-10?

Accepted Answer

A)  Steps 1-3 occur in the cytosol, while steps 6-10 occur in the mitochondrial matrix. 
B)  Steps 1-3 catalyze changes in a six-carbon molecule, while steps 6-10 catalyze changes in a four-carbon molecule. 
C)  Steps 1-3 catalyze reactions that require ATP, while steps 6-10 catalyze changes that require NADH. 
D)  Steps 1-3 catalyze reactions that require ATP, while steps 6-10 catalyze changes that produce NADH and GTP. 
E)  Steps 1-3 catalyze reactions that require ATP, while steps 6-10 catalyze changes that produce NADH and ATP. 
A)  Steps 1-3 occur in the cytosol, while steps 6-10 occur in the mitochondrial matrix. 
B)  Steps 1-3 catalyze changes in a six-carbon molecule, while steps 6-10 catalyze changes in a four-carbon molecule. 
C)  Steps 1-3 catalyze reactions that require ATP, while steps 6-10 catalyze changes that require NADH. 
D)  Steps 1-3 catalyze reactions that require ATP, while steps 6-10 catalyze changes that produce NADH and GTP. 
E)  Steps 1-3 catalyze reactions that require ATP, while steps 6-10 catalyze changes that produce NADH and ATP.

Question 12

In steps 6 through 10 of glycolysis, the conversion of 1 mole of glyceraldehyde 3-phosphate to pyruvate yields 2 moles of ATP.But the oxidation of glucose to pyruvate produces a total of 4 moles of ATP.Where do the remaining 2 moles of ATP come from?

Accepted Answer

A)  One mole of glucose yields 2 moles of glyceraldehyde 3-phosphate. 
B)  Two moles of ATP are used during the conversion of glucose to glyceraldehyde 3-phosphate. 
C)  Glycolysis produces 2 moles of NADH. 
D)  Fermentation of pyruvate to lactic acid yields 2 moles of ATP. 
E)  Fermentation of pyruvate to lactic acid yields 2 moles of NAD+. 
A)  One mole of glucose yields 2 moles of glyceraldehyde 3-phosphate. 
B)  Two moles of ATP are used during the conversion of glucose to glyceraldehyde 3-phosphate. 
C)  Glycolysis produces 2 moles of NADH. 
D)  Fermentation of pyruvate to lactic acid yields 2 moles of ATP. 
E)  Fermentation of pyruvate to lactic acid yields 2 moles of NAD+.

Question 13

Refer to the figure below.   Which two regulatory mechanisms are at work in the figure?

Accepted Answer

A)  Regulation by gene expression and by allosteric activators and inhibitors 
B)  Regulation by covalent modification and by allosteric activators and inhibitors 
C)  Regulation by gene expression and by positive feedback 
D)  Regulation by covalent modification and by negative feedback 
E)  Regulation by positive feedback and by allosteric activators and inhibitors 
A)  Regulation by gene expression and by allosteric activators and inhibitors 
B)  Regulation by covalent modification and by allosteric activators and inhibitors 
C)  Regulation by gene expression and by positive feedback 
D)  Regulation by covalent modification and by negative feedback 
E)  Regulation by positive feedback and by allosteric activators and inhibitors

Question 14

Data shown in the two graphs below are from experiments carried out on pyruvate dehydrogenase (PDH), the enzyme that catalyzes the conversion of pyruvate to acetyl CoA and carbon dioxide.   In the experiments, extracts of mitochondria were incubated for 6 minutes with high concentrations of ATP labeled with phosphorus-32.At various times, samples were removed and tested for PDH activity and incorporation of phosphorus-32 (32P) label into PDH.The results shown in the graphs suggest that PDH is regulated via a mechanism involving _______ of the PDH protein.

Accepted Answer

Question 15

The chemiosmotic generation of ATP is driven by

Accepted Answer

A)  osmotic movement of H2O into an area of high solute concentration. 
B)  the addition of protons to ADP and phosphate via enzymes. 
C)  oxidative phosphorylation. 
D)  the proton-motive force. 
E)  isocitrate dehydrogenase. 
A)  osmotic movement of H2O into an area of high solute concentration. 
B)  the addition of protons to ADP and phosphate via enzymes. 
C)  oxidative phosphorylation. 
D)  the proton-motive force. 
E)  isocitrate dehydrogenase.

Question 16

If the regeneration of NAD+ were inhibited during lactic acid fermentation, which of the following would likely occur?

Accepted Answer

A)  The rate of glucose converted to pyruvate would increase. 
B)  The rate of lactic acid production would decrease. 
C)  The rate of pyruvate production would remain the same. 
D)  The concentration of NAD+ would increase. 
E)  The concentration of ATP would increase. 
A)  The rate of glucose converted to pyruvate would increase. 
B)  The rate of lactic acid production would decrease. 
C)  The rate of pyruvate production would remain the same. 
D)  The concentration of NAD+ would increase. 
E)  The concentration of ATP would increase.

Question 17

Refer to the table below.   This table compares glucose oxidation carried out in a laboratory and in a living cell.To complete this table, _______ should be used to replace the question mark in the last column.

Accepted Answer

The answer of Refer to the table below.  ...

Question 18

When the supply of acetyl CoA being produced exceeds the demands of the citric acid cycle, some of the acetyl CoA is diverted to the synthesis of

Accepted Answer

A)  pyruvate. 
B)  NAD. 
C)  proteins. 
D)  fatty acids. 
E)  lactic acid. 
A)  pyruvate. 
B)  NAD. 
C)  proteins. 
D)  fatty acids. 
E)  lactic acid.

Question 19

Which is a viable path that a carbon atom could take as it moves through metabolic pathways in a cell?

Accepted Answer

A)  Amino acid F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 DNA F1F1F1S1F1F1F10F1F1F1S1F1F1F10purine F1F1F1S1F1F1F10 amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 triglyceride 
B)  Glucose F1F1F1S1F1F1F10 glycerol F1F1F1S1F1F1F10 triglyceride F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 DNA F1F1F1S1F1F1F10 pyrimidine F1F1F1S1F1F1F10 amino acid 
C)  Pyrimidine F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 glucose F1F1F1S1F1F1F10 pyruvate F1F1F1S1F1F1F10 lactic acid 
D)  Fatty acid F1F1F1S1F1F1F10 amino acid F1F1F1S1F1F1F10 pyrimidine F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 glucose F1F1F1S1F1F1F10 glycerol F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 amino acid 
E)  Amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 pyrimidine F1F1F1S1F1F1F10 glycerol F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 lactic acid F1F1F1S1F1F1F10 glucose 
A)  Amino acid F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 DNA F1F1F1S1F1F1F10F1F1F1S1F1F1F10purine F1F1F1S1F1F1F10 amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 triglyceride 
B)  Glucose F1F1F1S1F1F1F10 glycerol F1F1F1S1F1F1F10 triglyceride F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 DNA F1F1F1S1F1F1F10 pyrimidine F1F1F1S1F1F1F10 amino acid 
C)  Pyrimidine F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 glucose F1F1F1S1F1F1F10 pyruvate F1F1F1S1F1F1F10 lactic acid 
D)  Fatty acid F1F1F1S1F1F1F10 amino acid F1F1F1S1F1F1F10 pyrimidine F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 glucose F1F1F1S1F1F1F10 glycerol F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 amino acid 
E)  Amino acid F1F1F1S1F1F1F10 acetyl CoA F1F1F1S1F1F1F10 purine F1F1F1S1F1F1F10 pyrimidine F1F1F1S1F1F1F10 glycerol F1F1F1S1F1F1F10 fatty acid F1F1F1S1F1F1F10 lactic acid F1F1F1S1F1F1F10 glucose

Question 20

What is the net free energy captured by 32 moles of ATP?

Accepted Answer

A)  7.3 kcal 
B)  52.4 kcal 
C)  234 kcal 
D)  686 kcal 
E)  730 kcal 
A)  7.3 kcal 
B)  52.4 kcal 
C)  234 kcal 
D)  686 kcal 
E)  730 kcal

Exam 9: Pathways That Harvest Chemical Energy

Like glycolysis, fermentation occurs in the

Which statement about metabolic pathways is true?

Refer to the figure below, which shows an oxidation-reduction reaction that occurs spontaneously. Which statement correctly compares the free energy stored in molecules shown in the figure?

Which statement best describes steps 1, 2, and 3 of glycolysis (glucose  glucose 6-phosphate  fructose 1,6-bisphosphate)?

Refer to the figure below, showing inputs and outputs of glucose oxidation in a cell under aerobic conditions. Each box with a question mark should be labeled _______.

Refer to the figure below. This reaction links glycolysis to the citric acid cycle.Which statement correctly describes the chemical changes depicted in this reaction?

Under anaerobic conditions, pyruvate

The main difference between lactic acid fermentation and alcoholic fermentation is that lactic acid fermentation

Refer to the reaction below. Glyceraldehyde 3-phosphate (G3P) + NAD+ + H+ + Pi 1,3-bisphosphoglycerate (BPG) + NADH In this redox reaction, _______ is oxidized and _______ is reduced.

The link between glycolysis and the citric acid cycle is called _______.

How are steps 1-3 of glycolysis different from steps 6-10?

In steps 6 through 10 of glycolysis, the conversion of 1 mole of glyceraldehyde 3-phosphate to pyruvate yields 2 moles of ATP.But the oxidation of glucose to pyruvate produces a total of 4 moles of ATP.Where do the remaining 2 moles of ATP come from?

Refer to the figure below. Which two regulatory mechanisms are at work in the figure?

The chemiosmotic generation of ATP is driven by

If the regeneration of NAD+ were inhibited during lactic acid fermentation, which of the following would likely occur?

Refer to the table below. This table compares glucose oxidation carried out in a laboratory and in a living cell.To complete this table, _______ should be used to replace the question mark in the last column.

When the supply of acetyl CoA being produced exceeds the demands of the citric acid cycle, some of the acetyl CoA is diverted to the synthesis of

Which is a viable path that a carbon atom could take as it moves through metabolic pathways in a cell?

What is the net free energy captured by 32 moles of ATP?

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

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Ecosystems

A Changing Biosphere

Filters

Refer to the reaction below. Glyceraldehyde 3-phosphate (G3P) + NAD⁺ + H⁺ + P_i 1,3-bisphosphoglycerate (BPG) + NADH In this redox reaction, _ is oxidized and _ is reduced.

If the regeneration of NAD⁺ were inhibited during lactic acid fermentation, which of the following would likely occur?