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 researcher is studying a human cell in which the genetic material is
organized into chromosomes within a membrane-bound nucleus.
Which cellular structure is primarily responsible for maintaining and
transmitting the cell's hereditary information?
A. Lysosome
B. Genome
C. Golgi apparatus
D. Peroxisome
,Correct Answer: B. Genome
Rationale: The genome contains the complete genetic information
required for cellular structure, function, and reproduction. The
lysosome and peroxisome perform specialized metabolic functions,
while the Golgi apparatus modifies and sorts proteins. Thus, the
genome is the fundamental repository of hereditary information.
Question 2
A patient has a mutation affecting a gene that encodes a protein
required for DNA replication. Which cellular process would be most
directly impaired?
A. Protein secretion
B. Replication of genetic material
C. Degradation of damaged proteins
D. Oxidative phosphorylation
Correct Answer: B. Replication of genetic material
Rationale: A mutation in a DNA-replication protein directly
compromises the ability of the cell to duplicate its genome before
division. Protein secretion depends mainly on the endoplasmic
reticulum and Golgi apparatus, protein degradation involves pathways
such as the ubiquitin-proteasome system, and oxidative
phosphorylation occurs primarily in mitochondria.
Question 3
A hepatocyte synthesizes a protein that must remain within the cytosol
and function as an intracellular enzyme. Where would the protein most
likely be synthesized?
, A. Free ribosomes in the cytosol
B. Rough endoplasmic reticulum
C. Golgi apparatus
D. Lysosome
Correct Answer: A. Free ribosomes in the cytosol
Rationale: Proteins destined to function in the cytosol are generally
synthesized on free ribosomes. Ribosomes attached to the rough
endoplasmic reticulum synthesize proteins destined for secretion,
membranes, or certain organelles. The Golgi apparatus modifies and
sorts proteins rather than synthesizing them, and lysosomes contain
degradative enzymes.
Question 4
A cell contains large amounts of damaged or misfolded intracellular
proteins. Which cellular housekeeping mechanism is most directly
involved in selectively targeting many such proteins for degradation?
A. Ubiquitin-proteasome system
B. DNA replication
C. Glycolysis
D. Receptor-mediated signal transduction
Correct Answer: A. Ubiquitin-proteasome system
Rationale: The ubiquitin-proteasome pathway identifies many
damaged, misfolded, or short-lived intracellular proteins and directs
them to the proteasome for degradation. DNA replication duplicates
genetic material, glycolysis generates metabolic intermediates and ATP,
and signal transduction regulates cellular responses to external stimuli.
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 researcher is studying a human cell in which the genetic material is
organized into chromosomes within a membrane-bound nucleus.
Which cellular structure is primarily responsible for maintaining and
transmitting the cell's hereditary information?
A. Lysosome
B. Genome
C. Golgi apparatus
D. Peroxisome
,Correct Answer: B. Genome
Rationale: The genome contains the complete genetic information
required for cellular structure, function, and reproduction. The
lysosome and peroxisome perform specialized metabolic functions,
while the Golgi apparatus modifies and sorts proteins. Thus, the
genome is the fundamental repository of hereditary information.
Question 2
A patient has a mutation affecting a gene that encodes a protein
required for DNA replication. Which cellular process would be most
directly impaired?
A. Protein secretion
B. Replication of genetic material
C. Degradation of damaged proteins
D. Oxidative phosphorylation
Correct Answer: B. Replication of genetic material
Rationale: A mutation in a DNA-replication protein directly
compromises the ability of the cell to duplicate its genome before
division. Protein secretion depends mainly on the endoplasmic
reticulum and Golgi apparatus, protein degradation involves pathways
such as the ubiquitin-proteasome system, and oxidative
phosphorylation occurs primarily in mitochondria.
Question 3
A hepatocyte synthesizes a protein that must remain within the cytosol
and function as an intracellular enzyme. Where would the protein most
likely be synthesized?
, A. Free ribosomes in the cytosol
B. Rough endoplasmic reticulum
C. Golgi apparatus
D. Lysosome
Correct Answer: A. Free ribosomes in the cytosol
Rationale: Proteins destined to function in the cytosol are generally
synthesized on free ribosomes. Ribosomes attached to the rough
endoplasmic reticulum synthesize proteins destined for secretion,
membranes, or certain organelles. The Golgi apparatus modifies and
sorts proteins rather than synthesizing them, and lysosomes contain
degradative enzymes.
Question 4
A cell contains large amounts of damaged or misfolded intracellular
proteins. Which cellular housekeeping mechanism is most directly
involved in selectively targeting many such proteins for degradation?
A. Ubiquitin-proteasome system
B. DNA replication
C. Glycolysis
D. Receptor-mediated signal transduction
Correct Answer: A. Ubiquitin-proteasome system
Rationale: The ubiquitin-proteasome pathway identifies many
damaged, misfolded, or short-lived intracellular proteins and directs
them to the proteasome for degradation. DNA replication duplicates
genetic material, glycolysis generates metabolic intermediates and ATP,
and signal transduction regulates cellular responses to external stimuli.
