Robbins & Cotran 10th Ed. Pathology Test Bank | Chapter-
by-Chapter Questions & Verified Solutions
Robbins & Cotran Pathologic Basis of Disease
10th Edition
• Author(s)Vinay Kumar; Abul K. Abbas; Jon C. Aster
1. Chapter 1: The Genome – Noncoding DNA
A patient has a condition linked to dysregulation of gene
expression without a mutation in a protein-coding gene. The
clinician suspects a defect in the regulatory regions of the
genome. Which component of the human genome, comprising
the vast majority of its sequence, is primarily responsible for this
regulatory function?
A. Protein-coding exons
B. Introns within protein-coding genes
C. Noncoding DNA
D. Mitochondrial DNA (mtDNA)
Correct Answer: C
Rationale: Only about 1.5% of the human genome consists of
protein-coding exons. The remaining 98.5% is noncoding DNA,
which plays critical roles in the regulation of gene expression
,through mechanisms such as epigenetic modifications and
encoding regulatory RNAs . Options A and B are parts of genes
but represent a small fraction of the genome. Option D is not the
primary source of nuclear gene regulation.
Teaching Point: Noncoding DNA makes up most of the human
genome and is essential for regulating gene expression.
2. Chapter 1: Cellular Housekeeping – Protein Degradation
A new chemotherapeutic agent causes an accumulation of
misfolded proteins in the cell, leading to apoptosis. The drug is
most likely inhibiting which of the following cellular
housekeeping systems?
A. The ubiquitin-proteasome system
B. Autophagic vacuoles
C. Mitochondrial permeability transition
D. The Golgi apparatus
Correct Answer: A
Rationale: The ubiquitin-proteasome system is the primary
cellular machinery for the targeted degradation of misfolded and
short-lived proteins. Its impairment leads to the accumulation of
toxic protein aggregates, triggering cell death . While autophagy
(B) can degrade larger components, it is not the primary system
for individual misfolded proteins. Option C is involved in cell
death pathways, not protein degradation. Option D is involved in
protein modification and sorting.
Teaching Point: The ubiquitin-proteasome pathway is crucial
for eliminating misfolded proteins; its failure can induce cell
stress and death.
,3. Chapter 1: Cellular Metabolism and Mitochondrial
Function – Primary Role
A student is reviewing the fundamental roles of cellular
organelles. Which of the following is the primary and most
critical function of mitochondria in most eukaryotic cells?
A. Biosynthesis of nucleotides and amino acids
B. Storage and release of calcium ions
C. Generation of ATP through oxidative phosphorylation
D. Regulation of apoptotic cell death
Correct Answer: C
Rationale: While mitochondria perform many functions (A, B,
D), they are best known as the "powerhouses" of the cell
because their primary role is to generate the majority of the cell's
ATP through oxidative phosphorylation . This energy is
essential for all other cellular activities. The other options are
important but secondary functions.
Teaching Point: The primary function of mitochondria is ATP
production via oxidative phosphorylation, which supports all
cellular work.
4. Chapter 1: Cellular Metabolism and Mitochondrial
Function – mtDNA
A patient presents with a disease caused by a mutation in a gene
encoding a subunit of complex I of the electron transport chain.
This mutation was maternally inherited. Where is this gene
located?
A. Nuclear DNA
B. Mitochondrial DNA (mtDNA)
, C. Rough endoplasmic reticulum
D. Golgi apparatus
Correct Answer: B
Rationale: Mitochondrial DNA (mtDNA) encodes 13 proteins,
all of which are essential subunits of the electron transport chain
complexes (I, III, IV) and ATP synthase . mtDNA is maternally
inherited. Mutations in these genes cause specific mitochondrial
diseases. Nuclear DNA (A) encodes most mitochondrial
proteins, but those mutations follow Mendelian inheritance
patterns.
Teaching Point: mtDNA encodes key subunits of the oxidative
phosphorylation system, and its mutations are maternally
inherited.
5. Chapter 1: Cellular Activation – Signal Transduction
A growth factor binds to its receptor on a cell's surface,
activating a cascade where a series of intracellular proteins are
phosphorylated, ultimately changing gene expression in the
nucleus. This process is best described as:
A. Autocrine signaling
B. Signal transduction
C. Contact-dependent signaling
D. Second messenger activation
Correct Answer: B
Rationale: Signal transduction is the process by which an
extracellular signal (like a growth factor) is converted into an
intracellular response through a cascade of molecular events,
often involving phosphorylation . Autocrine signaling (A) is a
by-Chapter Questions & Verified Solutions
Robbins & Cotran Pathologic Basis of Disease
10th Edition
• Author(s)Vinay Kumar; Abul K. Abbas; Jon C. Aster
1. Chapter 1: The Genome – Noncoding DNA
A patient has a condition linked to dysregulation of gene
expression without a mutation in a protein-coding gene. The
clinician suspects a defect in the regulatory regions of the
genome. Which component of the human genome, comprising
the vast majority of its sequence, is primarily responsible for this
regulatory function?
A. Protein-coding exons
B. Introns within protein-coding genes
C. Noncoding DNA
D. Mitochondrial DNA (mtDNA)
Correct Answer: C
Rationale: Only about 1.5% of the human genome consists of
protein-coding exons. The remaining 98.5% is noncoding DNA,
which plays critical roles in the regulation of gene expression
,through mechanisms such as epigenetic modifications and
encoding regulatory RNAs . Options A and B are parts of genes
but represent a small fraction of the genome. Option D is not the
primary source of nuclear gene regulation.
Teaching Point: Noncoding DNA makes up most of the human
genome and is essential for regulating gene expression.
2. Chapter 1: Cellular Housekeeping – Protein Degradation
A new chemotherapeutic agent causes an accumulation of
misfolded proteins in the cell, leading to apoptosis. The drug is
most likely inhibiting which of the following cellular
housekeeping systems?
A. The ubiquitin-proteasome system
B. Autophagic vacuoles
C. Mitochondrial permeability transition
D. The Golgi apparatus
Correct Answer: A
Rationale: The ubiquitin-proteasome system is the primary
cellular machinery for the targeted degradation of misfolded and
short-lived proteins. Its impairment leads to the accumulation of
toxic protein aggregates, triggering cell death . While autophagy
(B) can degrade larger components, it is not the primary system
for individual misfolded proteins. Option C is involved in cell
death pathways, not protein degradation. Option D is involved in
protein modification and sorting.
Teaching Point: The ubiquitin-proteasome pathway is crucial
for eliminating misfolded proteins; its failure can induce cell
stress and death.
,3. Chapter 1: Cellular Metabolism and Mitochondrial
Function – Primary Role
A student is reviewing the fundamental roles of cellular
organelles. Which of the following is the primary and most
critical function of mitochondria in most eukaryotic cells?
A. Biosynthesis of nucleotides and amino acids
B. Storage and release of calcium ions
C. Generation of ATP through oxidative phosphorylation
D. Regulation of apoptotic cell death
Correct Answer: C
Rationale: While mitochondria perform many functions (A, B,
D), they are best known as the "powerhouses" of the cell
because their primary role is to generate the majority of the cell's
ATP through oxidative phosphorylation . This energy is
essential for all other cellular activities. The other options are
important but secondary functions.
Teaching Point: The primary function of mitochondria is ATP
production via oxidative phosphorylation, which supports all
cellular work.
4. Chapter 1: Cellular Metabolism and Mitochondrial
Function – mtDNA
A patient presents with a disease caused by a mutation in a gene
encoding a subunit of complex I of the electron transport chain.
This mutation was maternally inherited. Where is this gene
located?
A. Nuclear DNA
B. Mitochondrial DNA (mtDNA)
, C. Rough endoplasmic reticulum
D. Golgi apparatus
Correct Answer: B
Rationale: Mitochondrial DNA (mtDNA) encodes 13 proteins,
all of which are essential subunits of the electron transport chain
complexes (I, III, IV) and ATP synthase . mtDNA is maternally
inherited. Mutations in these genes cause specific mitochondrial
diseases. Nuclear DNA (A) encodes most mitochondrial
proteins, but those mutations follow Mendelian inheritance
patterns.
Teaching Point: mtDNA encodes key subunits of the oxidative
phosphorylation system, and its mutations are maternally
inherited.
5. Chapter 1: Cellular Activation – Signal Transduction
A growth factor binds to its receptor on a cell's surface,
activating a cascade where a series of intracellular proteins are
phosphorylated, ultimately changing gene expression in the
nucleus. This process is best described as:
A. Autocrine signaling
B. Signal transduction
C. Contact-dependent signaling
D. Second messenger activation
Correct Answer: B
Rationale: Signal transduction is the process by which an
extracellular signal (like a growth factor) is converted into an
intracellular response through a cascade of molecular events,
often involving phosphorylation . Autocrine signaling (A) is a
