Robbins Basic Pathology
10th Edition
Author(s)Vinay Kumar; Abul K. Abbas;
Jon C. Aster
TEST BANK
Reference
– Ch. 1 — The Cell as a Unit of Health and Disease — The
Genome
Question Stem
A 32-year-old woman is found to carry a heterozygous mutation
in a gene encoding a DNA repair enzyme. She has a modestly
increased cancer risk. Which explanation best links a germline
DNA-repair mutation to increased somatic mutations and
cancer risk?
,Options
A. The mutation increases transcriptional activity so oncogenes
are overexpressed.
B. Defective repair allows accumulation of replication errors
that become fixed as mutations.
C. The mutation causes immediate cell death of damaged cells,
leading to compensatory hyperplasia.
D. The mutation activates telomerase, preventing senescence
and causing unlimited proliferation.
Correct Answer
B
Rationales
Correct: Defective DNA-repair proteins permit replication errors
and damage to persist and be fixed as permanent mutations,
increasing cancer risk.
A: Increased transcription alone does not explain accumulation
of unrepaired DNA lesions causing mutations.
C: Immediate cell death would reduce, not increase, the pool of
mutated cells; compensatory hyperplasia is indirect.
D: Telomerase activation is a separate mechanism; DNA-repair
mutations do not directly induce telomerase.
Teaching Point
Impaired DNA repair → persistent replication errors → higher
somatic mutation burden.
Citation (simplified APA)
Kumar et al. (2021). Robbins Basic Pathology (10th Ed.). Ch. 1.
, 2.
Reference
– Ch. 1 — The Cell as a Unit of Health and Disease — The
Genome
Question Stem
A patient’s tumor sequencing shows microsatellite instability
(MSI). From a pathophysiologic standpoint, which cellular
defect most directly produces MSI?
Options
A. Failure of nucleotide excision repair to remove bulky adducts.
B. Defects in mismatch repair proteins that correct replication
slippage.
C. Loss of base excision repair leading to thymine dimers.
D. Dysfunctional homologous recombination preventing double-
strand break repair.
Correct Answer
B
Rationales
Correct: Microsatellite instability arises when mismatch repair
proteins fail to correct insertion/deletion errors at repetitive
sequences during replication.
A: Nucleotide excision repair removes bulky lesions (e.g., UV
adducts) not replication slippage at microsatellites.
C: Base excision repair handles small base lesions; thymine
, dimers are handled by nucleotide excision repair.
D: Homologous recombination repairs double-strand breaks,
not the replication slippage causing MSI.
Teaching Point
MSI = defective mismatch repair → errors at repetitive DNA
sequences.
Citation (simplified APA)
Kumar et al. (2021). Robbins Basic Pathology (10th Ed.). Ch. 1.
3.
Reference
– Ch. 1 — The Cell as a Unit of Health and Disease — Cellular
Housekeeping
Question Stem
A hospitalized patient develops accumulation of ubiquitinated
proteins in neurons. Which intracellular pathway dysfunction
best explains this finding?
Options
A. Impaired lysosomal acid hydrolases leading to defective
phagocytosis.
B. Dysfunction of the ubiquitin–proteasome system causing
failed degradation of short-lived proteins.
C. Overactive autophagy leading to excessive breakdown of
cytosolic proteins.
10th Edition
Author(s)Vinay Kumar; Abul K. Abbas;
Jon C. Aster
TEST BANK
Reference
– Ch. 1 — The Cell as a Unit of Health and Disease — The
Genome
Question Stem
A 32-year-old woman is found to carry a heterozygous mutation
in a gene encoding a DNA repair enzyme. She has a modestly
increased cancer risk. Which explanation best links a germline
DNA-repair mutation to increased somatic mutations and
cancer risk?
,Options
A. The mutation increases transcriptional activity so oncogenes
are overexpressed.
B. Defective repair allows accumulation of replication errors
that become fixed as mutations.
C. The mutation causes immediate cell death of damaged cells,
leading to compensatory hyperplasia.
D. The mutation activates telomerase, preventing senescence
and causing unlimited proliferation.
Correct Answer
B
Rationales
Correct: Defective DNA-repair proteins permit replication errors
and damage to persist and be fixed as permanent mutations,
increasing cancer risk.
A: Increased transcription alone does not explain accumulation
of unrepaired DNA lesions causing mutations.
C: Immediate cell death would reduce, not increase, the pool of
mutated cells; compensatory hyperplasia is indirect.
D: Telomerase activation is a separate mechanism; DNA-repair
mutations do not directly induce telomerase.
Teaching Point
Impaired DNA repair → persistent replication errors → higher
somatic mutation burden.
Citation (simplified APA)
Kumar et al. (2021). Robbins Basic Pathology (10th Ed.). Ch. 1.
, 2.
Reference
– Ch. 1 — The Cell as a Unit of Health and Disease — The
Genome
Question Stem
A patient’s tumor sequencing shows microsatellite instability
(MSI). From a pathophysiologic standpoint, which cellular
defect most directly produces MSI?
Options
A. Failure of nucleotide excision repair to remove bulky adducts.
B. Defects in mismatch repair proteins that correct replication
slippage.
C. Loss of base excision repair leading to thymine dimers.
D. Dysfunctional homologous recombination preventing double-
strand break repair.
Correct Answer
B
Rationales
Correct: Microsatellite instability arises when mismatch repair
proteins fail to correct insertion/deletion errors at repetitive
sequences during replication.
A: Nucleotide excision repair removes bulky lesions (e.g., UV
adducts) not replication slippage at microsatellites.
C: Base excision repair handles small base lesions; thymine
, dimers are handled by nucleotide excision repair.
D: Homologous recombination repairs double-strand breaks,
not the replication slippage causing MSI.
Teaching Point
MSI = defective mismatch repair → errors at repetitive DNA
sequences.
Citation (simplified APA)
Kumar et al. (2021). Robbins Basic Pathology (10th Ed.). Ch. 1.
3.
Reference
– Ch. 1 — The Cell as a Unit of Health and Disease — Cellular
Housekeeping
Question Stem
A hospitalized patient develops accumulation of ubiquitinated
proteins in neurons. Which intracellular pathway dysfunction
best explains this finding?
Options
A. Impaired lysosomal acid hydrolases leading to defective
phagocytosis.
B. Dysfunction of the ubiquitin–proteasome system causing
failed degradation of short-lived proteins.
C. Overactive autophagy leading to excessive breakdown of
cytosolic proteins.
