Question 1

What amount of free energy is released by the oxidation of 2 moles of NADH?

Accepted Answer

A)  7.3 kcal 
B)  14.6 kcal 
C)  21.9 kcal 
D)  52.4 kcal 
E)  104.8 kcal 
A)  7.3 kcal 
B)  14.6 kcal 
C)  21.9 kcal 
D)  52.4 kcal 
E)  104.8 kcal

Question 2

In eukaryotes, the organelle containing the enzyme(s) necessary for oxidation of glucose beyond glycolysis is the

Accepted Answer

A)  nucleus. 
B)  mitochondrion. 
C)  Golgi apparatus. 
D)  peroxisome. 
E)  lysosome. 
A)  nucleus. 
B)  mitochondrion. 
C)  Golgi apparatus. 
D)  peroxisome. 
E)  lysosome.

Question 3

Which is an example of a negative allosteric regulator of glycolysis or the citric acid cycle?

Accepted Answer

A)  ATP 
B)  Acetyl CoA 
C)  Citric acid 
D)  NAD+ 
E)  F1F1F1S1F1F1F10-Ketoglutarate 
A)  ATP 
B)  Acetyl CoA 
C)  Citric acid 
D)  NAD+ 
E)  F1F1F1S1F1F1F10-Ketoglutarate

Question 4

Key events in the rise of multicellularity in living organisms included the increase in _______ in/on Earth's _______ as a result of photosynthesis, and the evolution of _______ that enabled organisms to use _______.

Accepted Answer

A)  dry land; surface; lungs; oxygen 
B)  water; oceans; gills; oxygen 
C)  oxygen; atmosphere; cellular respiration; oxygen 
D)  carbon dioxide; atmosphere; photosynthesis; carbon dioxide 
E)  prey; ecosystems; primitive brains; fermentation 
A)  dry land; surface; lungs; oxygen 
B)  water; oceans; gills; oxygen 
C)  oxygen; atmosphere; cellular respiration; oxygen 
D)  carbon dioxide; atmosphere; photosynthesis; carbon dioxide 
E)  prey; ecosystems; primitive brains; fermentation

Question 5

A biochemist discovers several new microorganisms in a sample taken from the bottom of a deep lake in Antarctica.In characterizing one of these organisms, she finds that it cannot survive in an aerobic environment and produces lactic acid as a waste product.What is also likely true about this organism?

Accepted Answer

A)  It is able to oxidize pyruvate to acetyl CoA. 
B)  It is able to oxidize glucose to carbon dioxide. 
C)  It lacks genes for citric acid cycle enzymes. 
D)  It expresses all of the respiratory chain proteins. 
E)  It lacks genes for the glycolytic enzymes. 
A)  It is able to oxidize pyruvate to acetyl CoA. 
B)  It is able to oxidize glucose to carbon dioxide. 
C)  It lacks genes for citric acid cycle enzymes. 
D)  It expresses all of the respiratory chain proteins. 
E)  It lacks genes for the glycolytic enzymes.

Question 6

The chemiosmotic mechanism explains

Accepted Answer

A)  the coupling of glycolysis to the citric acid cycle. 
B)  how ATP is produced in the cytosol. 
C)  how water flows in and out of the mitochondria. 
D)  how a proton gradient is coupled to ATP production. 
E)  why membranes are not needed for ATP production. 
A)  the coupling of glycolysis to the citric acid cycle. 
B)  how ATP is produced in the cytosol. 
C)  how water flows in and out of the mitochondria. 
D)  how a proton gradient is coupled to ATP production. 
E)  why membranes are not needed for ATP production.

Question 7

Complete the following reaction found in the NADH shuttle mechanism in some eukaryotic cells: FAD + glycerol 3-ophsphate F1F1F1S1F1F1F10 _______ + DHAP.

Accepted Answer

A)  FADH 
B)  FADH2 
C)  FADH2 + NAD+ 
D)  FADH2 + NADH 
E)  glycerol 
A)  FADH 
B)  FADH2 
C)  FADH2 + NAD+ 
D)  FADH2 + NADH 
E)  glycerol

Question 8

Reagents, such as dinitrophenol, increase the permeability of the mitochondrial inner membrane to protons.The addition of dinitrophenol to a suspension of animal cells should

Accepted Answer

A)  decrease the rate of oxidation of NADH. 
B)  inhibit mitochondrial ATP synthesis. 
C)  increase lactic acid production. 
D)  decrease the rate of pyruvate oxidation. 
E)  stimulate ATP synthesis by mitochondria. 
A)  decrease the rate of oxidation of NADH. 
B)  inhibit mitochondrial ATP synthesis. 
C)  increase lactic acid production. 
D)  decrease the rate of pyruvate oxidation. 
E)  stimulate ATP synthesis by mitochondria.

Question 9

Products from the citric acid cycle include

Accepted Answer

A)  acetyl CoA. 
B)  NAD+. 
C)  FADH2. 
D)  ATP. 
E)  GDP. 
A)  acetyl CoA. 
B)  NAD+. 
C)  FADH2. 
D)  ATP. 
E)  GDP.

Question 10

Refer to the graph below.   Which statement about the respiratory chain best explains the information presented in the graph?

Accepted Answer

A)  During electron transport along the respiratory chain, protons are actively transported across the inner mitochondrial membrane to create a proton gradient. 
B)  The gradient of protons established across the inner mitochondrial membrane as a result of electron transport is a source of potential energy. 
C)  Extensive folding of the inner mitochondrial membrane allows a larger number of protein components in the respiratory chain than would otherwise fit. 
D)  The movement of protons from a high concentration in the intermembrane space to a low concentration in the mitochondrial matrix is coupled to the synthesis of ATP from ADP and Pi. 
E)  The components of the respiratory chain are arranged in order so that an electron passing from one to the next undergoes a sequential drop in energy. 
A)  During electron transport along the respiratory chain, protons are actively transported across the inner mitochondrial membrane to create a proton gradient. 
B)  The gradient of protons established across the inner mitochondrial membrane as a result of electron transport is a source of potential energy. 
C)  Extensive folding of the inner mitochondrial membrane allows a larger number of protein components in the respiratory chain than would otherwise fit. 
D)  The movement of protons from a high concentration in the intermembrane space to a low concentration in the mitochondrial matrix is coupled to the synthesis of ATP from ADP and Pi. 
E)  The components of the respiratory chain are arranged in order so that an electron passing from one to the next undergoes a sequential drop in energy.

Question 11

Refer to the graph below, showing changes in the source of blood glucose as a person goes from a state of active food intake to a state of starvation.   The person's blood glucose levels remain very stable; only the source of glucose changes.Liver cells play an active role in maintaining the stable levels of blood glucose.Which changes in liver cell metabolism could account for the data shown?

Accepted Answer

A)  At 1 hour after eating, liver cells inhibit phosphofructokinase and activate enzymes involved in glycogen breakdown. 
B)  At 4 hours after eating, liver cells activate enzymes involved in glycogen breakdown as well as enzymes involved in the breakdown of proteins and lipids. 
C)  At 10 hours after eating, liver cells activate fatty acid synthase and inhibit enzymes involved in the breakdown of proteins and lipids. 
D)  At 2 days into starvation, liver cells activate phosphofructokinase and inhibit enzymes involved in glycogen breakdown. 
E)  At 16 days into starvation, liver cells activate phosphofructokinase and inhibit enzymes involved in the breakdown of proteins and lipids. 
A)  At 1 hour after eating, liver cells inhibit phosphofructokinase and activate enzymes involved in glycogen breakdown. 
B)  At 4 hours after eating, liver cells activate enzymes involved in glycogen breakdown as well as enzymes involved in the breakdown of proteins and lipids. 
C)  At 10 hours after eating, liver cells activate fatty acid synthase and inhibit enzymes involved in the breakdown of proteins and lipids. 
D)  At 2 days into starvation, liver cells activate phosphofructokinase and inhibit enzymes involved in glycogen breakdown. 
E)  At 16 days into starvation, liver cells activate phosphofructokinase and inhibit enzymes involved in the breakdown of proteins and lipids.

Question 12

Cellular respiration refers to the metabolic process that

Accepted Answer

A)  involves the oxidation of glucose to pyruvate. 
B)  starts with sucrose. 
C)  produces 30 ATP. 
D)  releases less usable energy for a cell than fermentation. 
E)  involves the oxidation of pyruvate to carbon dioxide. 
A)  involves the oxidation of glucose to pyruvate. 
B)  starts with sucrose. 
C)  produces 30 ATP. 
D)  releases less usable energy for a cell than fermentation. 
E)  involves the oxidation of pyruvate to carbon dioxide.

Question 13

Refer to the figure below, showing the flux of carbon through metabolic pathways involving both the cytosol and mitochondria in a human muscle cell.The shade of the arrows (light and dark) is proportional to the rate of flux through that pathway.   Do you expect this cell to be undergoing rapid contractions or to be inactive, and what do you expect would change as the cell suddenly shifted into the opposite level of activity?

Accepted Answer

A)  The cell is inactive, and if called into high activity, it would shift metabolism of citrate through the citric acid cycle and electron transport, and away from fatty acid synthesis. 
B)  The cell is inactive, and if called into high activity, it would shift metabolism of citrate to synthesis of glucose via gluconeogenesis and away from fatty acid synthesis. 
C)  The cell is active, and if the cell became inactive, it would shift metabolism of citrate away from glucose and the citric acid cycle, and toward fatty acid synthesis. 
D)  The cell is active, and if the cell became inactive, it would shift metabolism of citrate through the citric acid cycle and electron transport, and away from fatty acid synthesis. 
E)  The cell is active, and if the cell became inactive, it would shift citrate toward synthesis of glucose via gluconeogenesis and away from fatty acid synthesis. 
A)  The cell is inactive, and if called into high activity, it would shift metabolism of citrate through the citric acid cycle and electron transport, and away from fatty acid synthesis. 
B)  The cell is inactive, and if called into high activity, it would shift metabolism of citrate to synthesis of glucose via gluconeogenesis and away from fatty acid synthesis. 
C)  The cell is active, and if the cell became inactive, it would shift metabolism of citrate away from glucose and the citric acid cycle, and toward fatty acid synthesis. 
D)  The cell is active, and if the cell became inactive, it would shift metabolism of citrate through the citric acid cycle and electron transport, and away from fatty acid synthesis. 
E)  The cell is active, and if the cell became inactive, it would shift citrate toward synthesis of glucose via gluconeogenesis and away from fatty acid synthesis.

Question 14

Which statement about metabolic pathways is incorrect?

Accepted Answer

A)  Chemical transformations occur in a series of separate chemical reactions. 
B)  A specific enzyme catalyzes each transformational step. 
C)  In eukaryotes, all metabolic reactions occur in the cytoplasm. 
D)  Inhibitors that target some key enzymes in a pathway can slow the rate of reaction. 
E)  Activators that target some key enzymes in a pathway can increase the rate of reaction. 
A)  Chemical transformations occur in a series of separate chemical reactions. 
B)  A specific enzyme catalyzes each transformational step. 
C)  In eukaryotes, all metabolic reactions occur in the cytoplasm. 
D)  Inhibitors that target some key enzymes in a pathway can slow the rate of reaction. 
E)  Activators that target some key enzymes in a pathway can increase the rate of reaction.

Question 15

The pyruvate dehydrogenase complex, a multienzyme complex in the citric acid cycle, is located in the

Accepted Answer

A)  thylakoids. 
B)  cytoplasm. 
C)  chloroplasts. 
D)  mitochondrial matrix. 
E)  cell membrane. 
A)  thylakoids. 
B)  cytoplasm. 
C)  chloroplasts. 
D)  mitochondrial matrix. 
E)  cell membrane.

Question 16

Refer to the diagram below, showing energy-releasing metabolic pathways.   Where in the cell is each step of the pathway located?

Accepted Answer

1: in the cytosol; 2: in the m

Question 17

The carbon end product of glycolysis is

Accepted Answer

A)  pyruvate. 
B)  carbon dioxide. 
C)  ethanol. 
D)  lactic acid. 
E)  ATP. 
A)  pyruvate. 
B)  carbon dioxide. 
C)  ethanol. 
D)  lactic acid. 
E)  ATP.

Question 18

Which statement about NADH is true?

Accepted Answer

A)  NADH is a coenzyme involved in glucose oxidation. 
B)  NADH is the reduced form of NAD+ from the addition of H+ and two electrons. 
C)  NADH is reduced by oxygen. 
D)  NADH is more electronegative than oxygen. 
E)  NADH stores less free energy per mole than ATP. 
A)  NADH is a coenzyme involved in glucose oxidation. 
B)  NADH is the reduced form of NAD+ from the addition of H+ and two electrons. 
C)  NADH is reduced by oxygen. 
D)  NADH is more electronegative than oxygen. 
E)  NADH stores less free energy per mole than ATP.

Question 19

In eukaryotes, the proton-motive force allows protons to move passively through ATP synthase in which direction?

Accepted Answer

A)  From the outside of the cell to the cytosol 
B)  From the mitochondrial matrix to the inner mitochondrial membrane space 
C)  From the cytoplasm to the mitochondrial matrix 
D)  From the cytoplasm to the mitochondrial inner membrane space 
E)  From the mitochondrial inner membrane space to the mitochondrial matrix 
A)  From the outside of the cell to the cytosol 
B)  From the mitochondrial matrix to the inner mitochondrial membrane space 
C)  From the cytoplasm to the mitochondrial matrix 
D)  From the cytoplasm to the mitochondrial inner membrane space 
E)  From the mitochondrial inner membrane space to the mitochondrial matrix

Question 20

Refer to the figure below.   How is this molecule involved in the cellular harvesting of energy from glucose oxidation?

Accepted Answer

A)  During the oxidation of glucose in a cell, this molecule is hydrolyzed to release the chemical energy in its phosphate bonds. 
B)  Electrons are removed from glucose and transferred to this molecule as a means of harvesting energy from glucose's chemical bonds. 
C)  This molecule transfers electrons to glucose in one step of the cellular glucose oxidation pathway. 
D)  Energy released during the cellular oxidation of glucose is used to add a phosphate to this molecule. 
E)  Oxygen accepts electrons from this molecule as the final step in the cellular oxidation of glucose. 
A)  During the oxidation of glucose in a cell, this molecule is hydrolyzed to release the chemical energy in its phosphate bonds. 
B)  Electrons are removed from glucose and transferred to this molecule as a means of harvesting energy from glucose's chemical bonds. 
C)  This molecule transfers electrons to glucose in one step of the cellular glucose oxidation pathway. 
D)  Energy released during the cellular oxidation of glucose is used to add a phosphate to this molecule. 
E)  Oxygen accepts electrons from this molecule as the final step in the cellular oxidation of glucose.

Exam 9: Pathways That Harvest Chemical Energy

What amount of free energy is released by the oxidation of 2 moles of NADH?

In eukaryotes, the organelle containing the enzyme(s) necessary for oxidation of glucose beyond glycolysis is the

Which is an example of a negative allosteric regulator of glycolysis or the citric acid cycle?

Key events in the rise of multicellularity in living organisms included the increase in _______ in/on Earth's _______ as a result of photosynthesis, and the evolution of _______ that enabled organisms to use _______.

The chemiosmotic mechanism explains

Complete the following reaction found in the NADH shuttle mechanism in some eukaryotic cells: FAD + glycerol 3-ophsphate  _______ + DHAP.

Reagents, such as dinitrophenol, increase the permeability of the mitochondrial inner membrane to protons.The addition of dinitrophenol to a suspension of animal cells should

Products from the citric acid cycle include

Refer to the graph below. Which statement about the respiratory chain best explains the information presented in the graph?

Cellular respiration refers to the metabolic process that

Which statement about metabolic pathways is incorrect?

The pyruvate dehydrogenase complex, a multienzyme complex in the citric acid cycle, is located in the

Refer to the diagram below, showing energy-releasing metabolic pathways. Where in the cell is each step of the pathway located?

The carbon end product of glycolysis is

Which statement about NADH is true?

In eukaryotes, the proton-motive force allows protons to move passively through ATP synthase in which direction?

Refer to the figure below. How is this molecule involved in the cellular harvesting of energy from glucose oxidation?

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

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Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

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Key events in the rise of multicellularity in living organisms included the increase in ___ in/on Earth's _ as a result of photosynthesis, and the evolution of _ that enabled organisms to use ___.