McCance & Huether’s Pathophysiology
The Biologic Basis for Disease in Adults and Children
9th Edition
• Author(s)Julia Rogers
TEST BANK
Chapter 1: Cellular Biology
1. Chapter 1, Cellular Communication and Signal Transduction
A researcher is studying a hormone that binds to a membrane-
bound receptor, activating a G-protein. This, in turn, activates
phospholipase C, leading to the release of calcium from
intracellular stores. This is an example of which type of signaling
mechanism?
A. Ligand-gated ion channel
B. Enzyme-linked receptor
C. G-protein–linked receptor
D. Integrin-linked receptor
Correct Answer: C
Rationale: C is correct because the description explicitly
involves a G-protein as the key second messenger system
activator, which is the hallmark of G-protein–linked receptor
signaling. A is incorrect because ligand-gated channels directly
,open an ion pore without a G-protein intermediary. B is
incorrect because enzyme-linked receptors (e.g., receptor
tyrosine kinases) typically involve direct phosphorylation
cascades. D is incorrect because integrin-linked receptors
primarily mediate signals about cell adhesion to the
extracellular matrix.
Teaching Point: G-protein–coupled receptors are a major class
of receptors that use second messengers like IP3 and DAG to
exert intracellular effects.
2. Chapter 1, Cellular Metabolism
A patient with a hereditary deficiency in the pyruvate
dehydrogenase complex would most likely experience impaired
production of which of the following molecules, which is the
final product of aerobic metabolism?
A. Lactic acid
B. Acetyl CoA
C. Pyruvic acid
D. Glucose-6-phosphate
Correct Answer: B
Rationale: B is correct because the pyruvate dehydrogenase
complex is the crucial link between glycolysis and the Krebs
cycle, catalyzing the irreversible conversion of pyruvate to
acetyl CoA. A is incorrect because a deficiency would cause
a build-up of pyruvate and its conversion to lactic acid, not an
impairment in its production. C is incorrect as pyruvate is the
,substrate, not the product, of this reaction. D is incorrect as
glucose-6-phosphate is involved in glycolysis and glycogen
metabolism, not the pyruvate-to-acetyl CoA step.
Teaching Point: Pyruvate dehydrogenase is the gatekeeper
enzyme for aerobic ATP production via the Krebs cycle and
electron transport chain.
3. Chapter 1, Structure and Function of Cellular Components
A cell biologist observes that a particular cell type is highly
active in detoxifying harmful substances like alcohol and
producing catalase. Which intracellular organelle is most
abundant and critical for this function?
A. Golgi apparatus
B. Rough endoplasmic reticulum
C. Peroxisome
D. Lysosome
Correct Answer: C
Rationale: C is correct because peroxisomes contain oxidases
(e.g., for alcohol) and catalase, which detoxify various
molecules and neutralize hydrogen peroxide. A is incorrect as
the Golgi apparatus is primarily involved in modifying and
packaging proteins. B is incorrect as the rough ER is involved in
protein synthesis. D is incorrect as lysosomes are involved in
intracellular digestion using hydrolytic enzymes.
Teaching Point: Peroxisomes are essential for the detoxification
of toxins and the breakdown of very long-chain fatty acids.
, 4. Chapter 1, Membrane Transport: Cellular Intake and Output
Glucose moves from the intestinal lumen into the epithelial cell
against its concentration gradient by coupling its transport with
the simultaneous movement of sodium ions down their
gradient. This process is best described as:
A. Simple diffusion
B. Facilitated diffusion
C. Primary active transport
D. Secondary active transport
Correct Answer: D
Rationale: D is correct because secondary active transport uses
the energy stored in an ion gradient (in this case, sodium),
which was established by primary active transport (Na+/K+
ATPase), to move another molecule against its gradient. A and B
are incorrect as they describe passive processes that do not
require energy and cannot move molecules against a gradient.
C is incorrect because primary active transport directly uses ATP
(e.g., the Na+/K+ pump itself).
Teaching Point: Secondary active transport harnesses the
energy of one ion's electrochemical gradient to power the
movement of another solute.
5. Chapter 1, Cellular Reproduction: The Cell Cycle
During which phase of the cell cycle does the cell undergo DNA
replication, resulting in the duplication of its genetic material?
The Biologic Basis for Disease in Adults and Children
9th Edition
• Author(s)Julia Rogers
TEST BANK
Chapter 1: Cellular Biology
1. Chapter 1, Cellular Communication and Signal Transduction
A researcher is studying a hormone that binds to a membrane-
bound receptor, activating a G-protein. This, in turn, activates
phospholipase C, leading to the release of calcium from
intracellular stores. This is an example of which type of signaling
mechanism?
A. Ligand-gated ion channel
B. Enzyme-linked receptor
C. G-protein–linked receptor
D. Integrin-linked receptor
Correct Answer: C
Rationale: C is correct because the description explicitly
involves a G-protein as the key second messenger system
activator, which is the hallmark of G-protein–linked receptor
signaling. A is incorrect because ligand-gated channels directly
,open an ion pore without a G-protein intermediary. B is
incorrect because enzyme-linked receptors (e.g., receptor
tyrosine kinases) typically involve direct phosphorylation
cascades. D is incorrect because integrin-linked receptors
primarily mediate signals about cell adhesion to the
extracellular matrix.
Teaching Point: G-protein–coupled receptors are a major class
of receptors that use second messengers like IP3 and DAG to
exert intracellular effects.
2. Chapter 1, Cellular Metabolism
A patient with a hereditary deficiency in the pyruvate
dehydrogenase complex would most likely experience impaired
production of which of the following molecules, which is the
final product of aerobic metabolism?
A. Lactic acid
B. Acetyl CoA
C. Pyruvic acid
D. Glucose-6-phosphate
Correct Answer: B
Rationale: B is correct because the pyruvate dehydrogenase
complex is the crucial link between glycolysis and the Krebs
cycle, catalyzing the irreversible conversion of pyruvate to
acetyl CoA. A is incorrect because a deficiency would cause
a build-up of pyruvate and its conversion to lactic acid, not an
impairment in its production. C is incorrect as pyruvate is the
,substrate, not the product, of this reaction. D is incorrect as
glucose-6-phosphate is involved in glycolysis and glycogen
metabolism, not the pyruvate-to-acetyl CoA step.
Teaching Point: Pyruvate dehydrogenase is the gatekeeper
enzyme for aerobic ATP production via the Krebs cycle and
electron transport chain.
3. Chapter 1, Structure and Function of Cellular Components
A cell biologist observes that a particular cell type is highly
active in detoxifying harmful substances like alcohol and
producing catalase. Which intracellular organelle is most
abundant and critical for this function?
A. Golgi apparatus
B. Rough endoplasmic reticulum
C. Peroxisome
D. Lysosome
Correct Answer: C
Rationale: C is correct because peroxisomes contain oxidases
(e.g., for alcohol) and catalase, which detoxify various
molecules and neutralize hydrogen peroxide. A is incorrect as
the Golgi apparatus is primarily involved in modifying and
packaging proteins. B is incorrect as the rough ER is involved in
protein synthesis. D is incorrect as lysosomes are involved in
intracellular digestion using hydrolytic enzymes.
Teaching Point: Peroxisomes are essential for the detoxification
of toxins and the breakdown of very long-chain fatty acids.
, 4. Chapter 1, Membrane Transport: Cellular Intake and Output
Glucose moves from the intestinal lumen into the epithelial cell
against its concentration gradient by coupling its transport with
the simultaneous movement of sodium ions down their
gradient. This process is best described as:
A. Simple diffusion
B. Facilitated diffusion
C. Primary active transport
D. Secondary active transport
Correct Answer: D
Rationale: D is correct because secondary active transport uses
the energy stored in an ion gradient (in this case, sodium),
which was established by primary active transport (Na+/K+
ATPase), to move another molecule against its gradient. A and B
are incorrect as they describe passive processes that do not
require energy and cannot move molecules against a gradient.
C is incorrect because primary active transport directly uses ATP
(e.g., the Na+/K+ pump itself).
Teaching Point: Secondary active transport harnesses the
energy of one ion's electrochemical gradient to power the
movement of another solute.
5. Chapter 1, Cellular Reproduction: The Cell Cycle
During which phase of the cell cycle does the cell undergo DNA
replication, resulting in the duplication of its genetic material?
