McCance & Huether’s Pathophysiology
The Biologic Basis for Disease in Adults and Children
9th Edition
• Author(s)Julia Rogers
TEST BANK
Question 1
Chapter 1, Cellular Communication and Signal Transduction
A researcher is studying a hormone that binds to a
transmembrane receptor, activating a G-protein. This G-protein
then directly stimulates the production of a second messenger
inside the cell. This is a classic example of which type of cellular
signaling?
A. Endocrine signaling
B. Autocrine signaling
C. Paracrine signaling
D. Contact-dependent signaling
Correct Answer: A. Endocrine signaling
Rationales:
Correct (A): Endocrine signaling involves hormones secreted
into the bloodstream by endocrine glands to act on distant
target cells. The description of hormone binding to a receptor
and using a G-protein/second messenger system (e.g., cAMP) is
a hallmark of this long-distance signaling method.
,Incorrect (B): Autocrine signaling occurs when a cell secretes a
signal that binds to receptors on its own surface, stimulating
itself.
Incorrect (C): Paracrine signaling involves local mediators
diffusing through the extracellular fluid to act on nearby cells,
not distant cells via the bloodstream.
Incorrect (D): Contact-dependent signaling requires direct
membrane-to-membrane contact between the signaling and
target cell, such as through gap junctions.
Teaching Point: Endocrine signals use circulating hormones and
intracellular second messengers to exert effects on distant
target cells.
Question 2
Chapter 1, Structure and Function of Cellular Components
A patient with a rare genetic disorder presents with recurrent
infections and neurological deficits. Lab tests reveal an
accumulation of undigested lipids and glycolipids in their cells.
A defect in which cellular organelle is most likely responsible for
this presentation?
A. Peroxisomes
B. Lysosomes
C. Mitochondria
D. Rough endoplasmic reticulum
Correct Answer: B. Lysosomes
,Rationales:
Correct (B): Lysosomes are membrane-bound organelles
containing digestive hydrolytic enzymes (acid hydrolases)
responsible for breaking down macromolecules like lipids,
carbohydrates, and proteins. A genetic defect in these enzymes
leads to the accumulation of undigested substrates, known as a
lysosomal storage disease.
Incorrect (A): Peroxisomes contain oxidases that break down
long-chain fatty acids and detoxify substances, but their
dysfunction does not typically cause lipid accumulation in this
manner.
Incorrect (C): Mitochondria are the powerhouses of the cell
responsible for ATP production via oxidative phosphorylation.
Defects cause energy deficits, not macromolecule
accumulation.
Incorrect (D): The rough endoplasmic reticulum is involved in
protein synthesis and processing, not the degradation of
cellular waste products.
Teaching Point: Lysosomal enzyme deficiencies cause storage
diseases due to the accumulation of undegraded substrates.
Question 3
Chapter 1, Cellular Metabolism
During intense exercise, skeletal muscle cells rapidly require
, large amounts of ATP. When oxygen demand outstrips supply,
which process becomes the primary source of ATP generation?
A. Oxidative phosphorylation
B. Beta-oxidation
C. Glycolysis
D. The Krebs cycle
Correct Answer: C. Glycolysis
Rationales:
Correct (C): Glycolysis is the anaerobic cytoplasmic pathway
that breaks down glucose into pyruvate, yielding a net gain of 2
ATP molecules per glucose without requiring oxygen. This is the
fastest way to generate ATP during hypoxic conditions.
Incorrect (A): Oxidative phosphorylation in the mitochondria is
highly efficient but requires oxygen as the final electron
acceptor. It cannot function anaerobically.
Incorrect (B): Beta-oxidation is the aerobic process of breaking
down fatty acids for the Krebs cycle and requires oxygen.
Incorrect (D): The Krebs cycle is an aerobic process that occurs
in the mitochondrial matrix and requires the products of
previous aerobic pathways.
Teaching Point: Glycolysis provides rapid ATP anaerobically, but
is inefficient compared to aerobic pathways.
Question 4
The Biologic Basis for Disease in Adults and Children
9th Edition
• Author(s)Julia Rogers
TEST BANK
Question 1
Chapter 1, Cellular Communication and Signal Transduction
A researcher is studying a hormone that binds to a
transmembrane receptor, activating a G-protein. This G-protein
then directly stimulates the production of a second messenger
inside the cell. This is a classic example of which type of cellular
signaling?
A. Endocrine signaling
B. Autocrine signaling
C. Paracrine signaling
D. Contact-dependent signaling
Correct Answer: A. Endocrine signaling
Rationales:
Correct (A): Endocrine signaling involves hormones secreted
into the bloodstream by endocrine glands to act on distant
target cells. The description of hormone binding to a receptor
and using a G-protein/second messenger system (e.g., cAMP) is
a hallmark of this long-distance signaling method.
,Incorrect (B): Autocrine signaling occurs when a cell secretes a
signal that binds to receptors on its own surface, stimulating
itself.
Incorrect (C): Paracrine signaling involves local mediators
diffusing through the extracellular fluid to act on nearby cells,
not distant cells via the bloodstream.
Incorrect (D): Contact-dependent signaling requires direct
membrane-to-membrane contact between the signaling and
target cell, such as through gap junctions.
Teaching Point: Endocrine signals use circulating hormones and
intracellular second messengers to exert effects on distant
target cells.
Question 2
Chapter 1, Structure and Function of Cellular Components
A patient with a rare genetic disorder presents with recurrent
infections and neurological deficits. Lab tests reveal an
accumulation of undigested lipids and glycolipids in their cells.
A defect in which cellular organelle is most likely responsible for
this presentation?
A. Peroxisomes
B. Lysosomes
C. Mitochondria
D. Rough endoplasmic reticulum
Correct Answer: B. Lysosomes
,Rationales:
Correct (B): Lysosomes are membrane-bound organelles
containing digestive hydrolytic enzymes (acid hydrolases)
responsible for breaking down macromolecules like lipids,
carbohydrates, and proteins. A genetic defect in these enzymes
leads to the accumulation of undigested substrates, known as a
lysosomal storage disease.
Incorrect (A): Peroxisomes contain oxidases that break down
long-chain fatty acids and detoxify substances, but their
dysfunction does not typically cause lipid accumulation in this
manner.
Incorrect (C): Mitochondria are the powerhouses of the cell
responsible for ATP production via oxidative phosphorylation.
Defects cause energy deficits, not macromolecule
accumulation.
Incorrect (D): The rough endoplasmic reticulum is involved in
protein synthesis and processing, not the degradation of
cellular waste products.
Teaching Point: Lysosomal enzyme deficiencies cause storage
diseases due to the accumulation of undegraded substrates.
Question 3
Chapter 1, Cellular Metabolism
During intense exercise, skeletal muscle cells rapidly require
, large amounts of ATP. When oxygen demand outstrips supply,
which process becomes the primary source of ATP generation?
A. Oxidative phosphorylation
B. Beta-oxidation
C. Glycolysis
D. The Krebs cycle
Correct Answer: C. Glycolysis
Rationales:
Correct (C): Glycolysis is the anaerobic cytoplasmic pathway
that breaks down glucose into pyruvate, yielding a net gain of 2
ATP molecules per glucose without requiring oxygen. This is the
fastest way to generate ATP during hypoxic conditions.
Incorrect (A): Oxidative phosphorylation in the mitochondria is
highly efficient but requires oxygen as the final electron
acceptor. It cannot function anaerobically.
Incorrect (B): Beta-oxidation is the aerobic process of breaking
down fatty acids for the Krebs cycle and requires oxygen.
Incorrect (D): The Krebs cycle is an aerobic process that occurs
in the mitochondrial matrix and requires the products of
previous aerobic pathways.
Teaching Point: Glycolysis provides rapid ATP anaerobically, but
is inefficient compared to aerobic pathways.
Question 4
