Robbins Basic Pathology
10th Edition
Author(s)Vinay Kumar; MBBS; MD;
FRCPath; Abul K. Abbas; MBBS and
Jon C. Aster; MD; PhD
Print ISBN: 9780323353175
,Question 1
A patient has a germline mutation that prevents accurate DNA
replication. Which cellular process is most directly affected by this
defect?
A. Transmission of genetic information to daughter cells
B. Synthesis of ATP by oxidative phosphorylation
C. Secretion of extracellular matrix proteins
D. Activation of plasma membrane receptors
,Correct Answer: A. Transmission of genetic information to daughter
cells
Rationale: Accurate DNA replication is essential for preserving and
transmitting the genome during cell division. A defect in replication can
produce mutations or chromosome abnormalities in daughter cells. B is
primarily a mitochondrial function, C involves protein synthesis and
secretion, and D concerns signal transduction rather than genome
duplication.
Question 2
A hepatocyte continuously synthesizes proteins that will be secreted
into the bloodstream. Which organelle is most directly responsible for
translating these proteins?
A. Smooth endoplasmic reticulum
B. Rough endoplasmic reticulum
C. Golgi apparatus
D. Lysosome
Correct Answer: B. Rough endoplasmic reticulum
Rationale: Proteins destined for secretion are synthesized by ribosomes
attached to the rough endoplasmic reticulum. The newly synthesized
proteins then enter the secretory pathway for processing and transport.
The smooth endoplasmic reticulum is important in lipid synthesis and
detoxification, the Golgi apparatus modifies and sorts proteins, and
lysosomes digest intracellular material.
Question 3
, A cell exposed to prolonged metabolic stress begins to accumulate
misfolded proteins within the endoplasmic reticulum. Which cellular
response is most appropriate initially?
A. Activation of mechanisms that increase protein folding and reduce
protein synthesis
B. Immediate rupture of the plasma membrane
C. Increased mitochondrial DNA replication
D. Permanent arrest of all cellular metabolism
Correct Answer: A. Activation of mechanisms that increase protein
folding and reduce protein synthesis
Rationale: Accumulation of unfolded or misfolded proteins activates the
unfolded protein response, which attempts to restore cellular
homeostasis by enhancing protein-folding capacity and reducing the
load of newly synthesized proteins. Plasma membrane rupture is
associated with severe cell injury, not an early adaptive response.
Mitochondrial DNA replication does not directly correct endoplasmic
reticulum stress, and metabolism is not universally halted.
Question 4
Which organelle contains hydrolytic enzymes that digest damaged
cellular components and materials taken up by endocytosis?
A. Peroxisome
B. Ribosome
C. Lysosome
D. Mitochondrion
Correct Answer: C. Lysosome
10th Edition
Author(s)Vinay Kumar; MBBS; MD;
FRCPath; Abul K. Abbas; MBBS and
Jon C. Aster; MD; PhD
Print ISBN: 9780323353175
,Question 1
A patient has a germline mutation that prevents accurate DNA
replication. Which cellular process is most directly affected by this
defect?
A. Transmission of genetic information to daughter cells
B. Synthesis of ATP by oxidative phosphorylation
C. Secretion of extracellular matrix proteins
D. Activation of plasma membrane receptors
,Correct Answer: A. Transmission of genetic information to daughter
cells
Rationale: Accurate DNA replication is essential for preserving and
transmitting the genome during cell division. A defect in replication can
produce mutations or chromosome abnormalities in daughter cells. B is
primarily a mitochondrial function, C involves protein synthesis and
secretion, and D concerns signal transduction rather than genome
duplication.
Question 2
A hepatocyte continuously synthesizes proteins that will be secreted
into the bloodstream. Which organelle is most directly responsible for
translating these proteins?
A. Smooth endoplasmic reticulum
B. Rough endoplasmic reticulum
C. Golgi apparatus
D. Lysosome
Correct Answer: B. Rough endoplasmic reticulum
Rationale: Proteins destined for secretion are synthesized by ribosomes
attached to the rough endoplasmic reticulum. The newly synthesized
proteins then enter the secretory pathway for processing and transport.
The smooth endoplasmic reticulum is important in lipid synthesis and
detoxification, the Golgi apparatus modifies and sorts proteins, and
lysosomes digest intracellular material.
Question 3
, A cell exposed to prolonged metabolic stress begins to accumulate
misfolded proteins within the endoplasmic reticulum. Which cellular
response is most appropriate initially?
A. Activation of mechanisms that increase protein folding and reduce
protein synthesis
B. Immediate rupture of the plasma membrane
C. Increased mitochondrial DNA replication
D. Permanent arrest of all cellular metabolism
Correct Answer: A. Activation of mechanisms that increase protein
folding and reduce protein synthesis
Rationale: Accumulation of unfolded or misfolded proteins activates the
unfolded protein response, which attempts to restore cellular
homeostasis by enhancing protein-folding capacity and reducing the
load of newly synthesized proteins. Plasma membrane rupture is
associated with severe cell injury, not an early adaptive response.
Mitochondrial DNA replication does not directly correct endoplasmic
reticulum stress, and metabolism is not universally halted.
Question 4
Which organelle contains hydrolytic enzymes that digest damaged
cellular components and materials taken up by endocytosis?
A. Peroxisome
B. Ribosome
C. Lysosome
D. Mitochondrion
Correct Answer: C. Lysosome
