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
Chapter 1 — The Genome
Question 1 (The Genome)
A 28-year-old woman undergoes genetic testing after recurrent
early miscarriages. Her clinician explains that some noncoding
regions of the genome regulate gene expression without
encoding protein. Which mechanism best describes how
noncoding DNA can influence gene transcription?
A. Noncoding DNA directly encodes tRNAs that increase mRNA
translation.
B. Noncoding DNA is transcribed to regulatory RNAs and sites
for chromatin modification that modulate transcription.
C. Noncoding DNA serves only as evolutionary “junk” and has
no regulatory role.
D. Noncoding DNA is universally methylated and permanently
silences nearby genes.
,Correct Answer: B
Rationale — correct: Robbins explains that much noncoding
DNA has regulatory functions — producing noncoding RNAs
(e.g., miRNAs, lncRNAs) and providing binding sites for
chromatin modifiers that influence transcriptional activity.
ClinicalKey
Option A (wrong): While tRNAs are transcribed, most
noncoding regulatory regions do not function by encoding tRNA
to enhance translation; their primary role is
transcriptional/post-transcriptional regulation. ClinicalKey
Option C (wrong): Robbins rejects the “junk DNA” idea — many
noncoding elements have regulatory roles. ClinicalKey
Option D (wrong): DNA methylation can silence genes in some
contexts but noncoding regions are not universally methylated;
methylation is dynamic and context-dependent. ClinicalKey
Teaching Point: Noncoding genomic regions regulate gene
expression via RNAs and chromatin interactions. ClinicalKey
1 — The Genome
Question 2 (The Genome)
A patient’s tumor shows loss of function in a DNA mismatch–
repair gene. Which genomic consequence most directly
increases the tumor’s mutation burden?
A. Increased chromosomal translocations due to double-strand
breaks.
,B. Accumulation of single-base mismatches and microsatellite
instability.
C. Increased frequency of retrotransposon insertions.
D. Global loss of CpG islands across the genome.
Correct Answer: B
Rationale — correct: Robbins describes that defective
mismatch-repair causes accumulation of base mismatches and
microsatellite instability, raising mutation burden. ClinicalKey
Option A (wrong): Double-strand break repair defects cause
translocations, but mismatch repair defects primarily cause
base-pair errors and microsatellite instability. ClinicalKey
Option C (wrong): Retrotransposition occurs but is not the
hallmark consequence of mismatch-repair deficiency.
ClinicalKey
Option D (wrong): CpG island methylation changes are
epigenetic events; mismatch-repair loss doesn’t directly cause
global CpG loss. ClinicalKey
Teaching Point: Mismatch-repair defects → base errors and
microsatellite instability, increasing mutation load. ClinicalKey
1 — The Genome
Question 3 (The Genome)
A newborn screening identifies a pathogenic point mutation in
a mitochondrial gene. Which statement about mitochondrial
inheritance and genome is most accurate?
, A. Mitochondrial DNA is inherited equally from both parents
and follows Mendelian rules.
B. Mitochondria lack any genes involved in oxidative
phosphorylation.
C. Mitochondrial DNA is maternally inherited, and
heteroplasmy can cause variable expression.
D. All mitochondria within a cell have genetically identical
genomes always.
Correct Answer: C
Rationale — correct: Robbins notes mitochondrial DNA is
maternally inherited; heteroplasmy (mixed mutant and wild-
type mtDNA) underlies variable clinical expression. ClinicalKey
Option A (wrong): Mitochondrial DNA is typically maternally
inherited and does not follow Mendelian nuclear inheritance.
ClinicalKey
Option B (wrong): Mitochondrial DNA encodes key subunits of
oxidative phosphorylation complexes. ClinicalKey
Option D (wrong): Heteroplasmy means different mitochondria
can carry different genomes within the same cell. ClinicalKey
Teaching Point: Mitochondrial disorders reflect maternal
inheritance and heteroplasmy. ClinicalKey
2 — Cellular Housekeeping
Question 4 (Cellular Housekeeping)
A hospitalized patient receives a drug that inhibits the 26S
by-Chapter Questions & Verified Solutions
Robbins & Cotran Pathologic Basis of Disease
10th Edition
• Author(s)Vinay Kumar; Abul K. Abbas; Jon C. Aster
Chapter 1 — The Genome
Question 1 (The Genome)
A 28-year-old woman undergoes genetic testing after recurrent
early miscarriages. Her clinician explains that some noncoding
regions of the genome regulate gene expression without
encoding protein. Which mechanism best describes how
noncoding DNA can influence gene transcription?
A. Noncoding DNA directly encodes tRNAs that increase mRNA
translation.
B. Noncoding DNA is transcribed to regulatory RNAs and sites
for chromatin modification that modulate transcription.
C. Noncoding DNA serves only as evolutionary “junk” and has
no regulatory role.
D. Noncoding DNA is universally methylated and permanently
silences nearby genes.
,Correct Answer: B
Rationale — correct: Robbins explains that much noncoding
DNA has regulatory functions — producing noncoding RNAs
(e.g., miRNAs, lncRNAs) and providing binding sites for
chromatin modifiers that influence transcriptional activity.
ClinicalKey
Option A (wrong): While tRNAs are transcribed, most
noncoding regulatory regions do not function by encoding tRNA
to enhance translation; their primary role is
transcriptional/post-transcriptional regulation. ClinicalKey
Option C (wrong): Robbins rejects the “junk DNA” idea — many
noncoding elements have regulatory roles. ClinicalKey
Option D (wrong): DNA methylation can silence genes in some
contexts but noncoding regions are not universally methylated;
methylation is dynamic and context-dependent. ClinicalKey
Teaching Point: Noncoding genomic regions regulate gene
expression via RNAs and chromatin interactions. ClinicalKey
1 — The Genome
Question 2 (The Genome)
A patient’s tumor shows loss of function in a DNA mismatch–
repair gene. Which genomic consequence most directly
increases the tumor’s mutation burden?
A. Increased chromosomal translocations due to double-strand
breaks.
,B. Accumulation of single-base mismatches and microsatellite
instability.
C. Increased frequency of retrotransposon insertions.
D. Global loss of CpG islands across the genome.
Correct Answer: B
Rationale — correct: Robbins describes that defective
mismatch-repair causes accumulation of base mismatches and
microsatellite instability, raising mutation burden. ClinicalKey
Option A (wrong): Double-strand break repair defects cause
translocations, but mismatch repair defects primarily cause
base-pair errors and microsatellite instability. ClinicalKey
Option C (wrong): Retrotransposition occurs but is not the
hallmark consequence of mismatch-repair deficiency.
ClinicalKey
Option D (wrong): CpG island methylation changes are
epigenetic events; mismatch-repair loss doesn’t directly cause
global CpG loss. ClinicalKey
Teaching Point: Mismatch-repair defects → base errors and
microsatellite instability, increasing mutation load. ClinicalKey
1 — The Genome
Question 3 (The Genome)
A newborn screening identifies a pathogenic point mutation in
a mitochondrial gene. Which statement about mitochondrial
inheritance and genome is most accurate?
, A. Mitochondrial DNA is inherited equally from both parents
and follows Mendelian rules.
B. Mitochondria lack any genes involved in oxidative
phosphorylation.
C. Mitochondrial DNA is maternally inherited, and
heteroplasmy can cause variable expression.
D. All mitochondria within a cell have genetically identical
genomes always.
Correct Answer: C
Rationale — correct: Robbins notes mitochondrial DNA is
maternally inherited; heteroplasmy (mixed mutant and wild-
type mtDNA) underlies variable clinical expression. ClinicalKey
Option A (wrong): Mitochondrial DNA is typically maternally
inherited and does not follow Mendelian nuclear inheritance.
ClinicalKey
Option B (wrong): Mitochondrial DNA encodes key subunits of
oxidative phosphorylation complexes. ClinicalKey
Option D (wrong): Heteroplasmy means different mitochondria
can carry different genomes within the same cell. ClinicalKey
Teaching Point: Mitochondrial disorders reflect maternal
inheritance and heteroplasmy. ClinicalKey
2 — Cellular Housekeeping
Question 4 (Cellular Housekeeping)
A hospitalized patient receives a drug that inhibits the 26S
