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.
1. . Chapter 1 — Prokaryotes and Eukaryotes: Distinguishing
cellular organization
Stem: A hospitalized patient has a severe bacterial bloodstream
infection. Which cellular feature of the causative organism most
clearly distinguishes it as a prokaryote rather than a eukaryote?
Options:
A) Presence of membrane-bound nucleus
B) Lack of membrane-bound organelles
C) Presence of a linear chromosome
D) Presence of a mitochondrion
Correct Answer: B
,Rationales:
Correct: Prokaryotes lack membrane-bound organelles
(including a nucleus and mitochondria) and have simpler
internal structures; this is a fundamental distinguishing feature
between prokaryotes and eukaryotes.
Incorrect A: A membrane-bound nucleus is characteristic of
eukaryotes, not prokaryotes, so its presence would not indicate
a prokaryote.
Incorrect C: Prokaryotes typically have a single circular
chromosome, not a linear chromosome; linear chromosomes
are more typical of eukaryotes.
Incorrect D: Mitochondria are membrane-bound organelles
found in eukaryotes; prokaryotes lack mitochondria.
Teaching Point: Prokaryotes lack membrane-bound organelles
such as a nucleus and mitochondria.
2. Chapter 1 — Cellular Functions: Homeostasis and cell
specialization
Stem: A renal tubular cell increases expression of transport
proteins after sustained exposure to a high-sodium diet. This
adaptation best exemplifies which cellular function?
Options:
A) Cell differentiation
B) Cellular adaptation via upregulation
C) Apoptosis
D) Oncogenesis
,Correct Answer: B
Rationales:
Correct: Upregulation of transport proteins in response to
increased load is an adaptive cellular response to maintain
homeostasis; this is a regulated increase in functional capacity.
Incorrect A: Cell differentiation refers to development into a
specialized cell type, not an acute adaptive increase in protein
expression.
Incorrect C: Apoptosis is programmed cell death and is not an
adaptive increase in transport function.
Incorrect D: Oncogenesis refers to malignant transformation,
unrelated to physiologic upregulation of transporters.
Teaching Point: Cells adapt to increased functional demand by
upregulating relevant proteins.
3. Chapter 1 — Structure and Function of Cellular
Components: Plasma membrane role
Stem: A drug is highly lipophilic and crosses cell membranes
easily by passive diffusion. Which property of the plasma
membrane primarily allows this drug to enter cells?
Options:
A) Presence of transmembrane carrier proteins
B) Lipid bilayer with hydrophobic core
C) Glycocalyx on the external surface
D) Tight junctions between adjacent cells
, Correct Answer: B
Rationales:
Correct: The plasma membrane’s lipid bilayer has a hydrophobic
core that permits diffusion of lipophilic molecules across the
membrane down a concentration gradient.
Incorrect A: Carrier proteins mediate facilitated transport for
specific molecules but are not required for passive diffusion of
lipophilic drugs.
Incorrect C: The glycocalyx is a carbohydrate-rich external layer
involved in cell recognition and protection, not passive lipid
diffusion.
Incorrect D: Tight junctions connect adjacent cells and regulate
paracellular transport but do not determine transmembrane
diffusion of lipophilic drugs.
Teaching Point: Lipophilic molecules cross membranes via the
bilayer’s hydrophobic core.
4. Chapter 1 — Structure and Function of Cellular
Components: Mitochondrial dysfunction
Stem: A patient with mitochondrial myopathy has exercise
intolerance and lactic acidosis. Which mitochondrial defect best
explains increased lactate during exertion?
Options:
A) Impaired oxidative phosphorylation (electron transport
chain)