The Biologic Basis for Disease in Adults and Children
9th Edition
• Author(s)Julia Rogers
TEST BANK
McCance & Huether — Pathophysiology, 9th Ed. — Chapter 1:
Cellular Biology.
Chapter Reference: Chapter 1 — Cellular Biology; Section:
Prokaryotes and Eukaryotes; Title: Cellular Organization and
Genetic Material
Stem: A microbiology lab receives an unknown bacterial isolate.
Under light microscopy you detect no membrane-bound
nucleus and small 70S ribosomes; biochemical testing shows
peptidoglycan in the cell wall. Which feature most reliably
classifies this organism as a prokaryote rather than a
eukaryote?
Options:
A. Presence of membrane-bound mitochondria
B. Lack of a membrane-bound nucleus
,C. Larger ribosomes (80S)
D. Organized nuclear chromatin
Correct Answer: B
Rationales:
Correct: Lack of a membrane-bound nucleus is the defining trait
of prokaryotes; their DNA is in a nucleoid not enclosed by a
nuclear membrane.
A incorrect: Presence of mitochondria indicates eukaryotes;
absence does not exclusively prove prokaryote (some
eukaryotes can lack typical mitochondria-like organelles).
C incorrect: Small 70S ribosomes are characteristic of
prokaryotes, but the presence/absence of a nucleus is the more
definitive organizational difference.
D incorrect: Organized nuclear chromatin is a eukaryotic feature
and not seen in prokaryotes, but "lack of nucleus" is the
succinct classifier.
Teaching Point: Prokaryotes are defined primarily by absence of
a membrane-bound nucleus.
Stem Rules: 1–2 sentence clinical/lab vignette; single clear
question; avoids negatives.
2.
Chapter Reference: Chapter 1 — Cellular Biology; Section:
Prokaryotes and Eukaryotes; Title: Comparative Cellular
Structures
,Stem: A researcher compares human hepatocytes and bacterial
cells. Which difference explains why antibiotics targeting
bacterial 70S ribosomes spare human cells?
Options:
A. Bacterial ribosomes are membrane-bound.
B. Bacterial ribosomes are structurally distinct 70S particles.
C. Human ribosomes are more numerous.
D. Human ribosomes synthesize different amino acids.
Correct Answer: B
Rationales:
Correct: Bacterial ribosomes are 70S (30S+50S) with structural
differences that many antibiotics exploit, whereas eukaryotic
ribosomes are 80S.
A incorrect: Ribosomes are not membrane-bound in bacteria;
membrane association is irrelevant to antibiotic selectivity.
C incorrect: Number of ribosomes does not explain selective
drug binding — structure does.
D incorrect: Ribosomes synthesize the same standard amino
acids; selectivity arises from ribosomal structural differences.
Teaching Point: Antibiotics exploit structural differences
between 70S and 80S ribosomes.
Stem Rules: Short comparative stem; mechanistic focus.
3.
, Chapter Reference: Chapter 1 — Cellular Biology; Section:
Cellular Functions; Title: Homeostasis and Cellular Adaptation
Stem: A patient with chronic bronchial irritation develops
squamous metaplasia of tracheal epithelium. Which statement
best explains metaplasia?
Options:
A. Permanent loss of all cellular function due to necrosis
B. Replacement of one differentiated cell type by another
adaptive type
C. Uncontrolled proliferation with invasion of neighboring
tissues
D. Immediate apoptosis of damaged epithelial cells
Correct Answer: B
Rationales:
Correct: Metaplasia is an adaptive, reversible change where one
mature cell type is replaced by another better suited to chronic
stress (e.g., columnar → squamous in smokers).
A incorrect: Necrosis is cell death, not adaptive replacement;
metaplasia preserves viable cells.
C incorrect: That describes malignant transformation, not
metaplasia which is non-neoplastic and usually reversible.
D incorrect: Apoptosis is programmed death; metaplasia
involves phenotypic change, not immediate cell death.