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 examines a normal human somatic cell and asks where
most of the cell's genomic DNA is located. Which structure contains the
greatest amount of this DNA?
A. Golgi apparatus
B. Nucleus
C. Lysosome
D. Plasma membrane
Correct Answer: B. Nucleus
,Rationale:
The nucleus contains the vast majority of the cell's genomic DNA
organized into chromosomes. The Golgi apparatus and lysosomes
contain proteins and other cellular components but do not house the
nuclear genome. The plasma membrane contains receptors, lipids, and
transport proteins but essentially no genomic DNA.
Question 2
A normal cell is maintaining its internal environment by regulating ion
concentrations, pH, and protein turnover despite continuous changes in
the extracellular environment. Which term best describes this
property?
A. Homeostasis
B. Metastasis
C. Differentiation
D. Senescence
Correct Answer: A. Homeostasis
Rationale:
Homeostasis refers to the ability of a cell or organism to maintain a
relatively stable internal environment despite external changes.
Differentiation refers to acquisition of specialized cellular
characteristics, whereas senescence is a state of essentially permanent
cell-cycle arrest. Metastasis describes dissemination of malignant cells
and is unrelated to routine cellular regulation.
Question 3
A mutation prevents a cellular protein from being correctly folded in the
endoplasmic reticulum. Which cellular process is most directly
, responsible for identifying and disposing of many such abnormal
proteins?
A. Protein degradation through quality-control pathways
B. DNA replication
C. Exocytosis of intact chromosomes
D. Extracellular matrix synthesis
Correct Answer: A. Protein degradation through quality-control
pathways
Rationale:
Cells use protein-quality-control mechanisms to recognize misfolded or
damaged proteins and target them for degradation, helping preserve
cellular function. DNA replication produces new copies of genetic
material and does not remove misfolded proteins. Exocytosis does not
expel chromosomes, and extracellular matrix synthesis produces
structural proteins outside the cell rather than degrading defective
intracellular proteins.
Question 4
A hepatocyte requires ATP to power ion pumps that maintain its
membrane potential. Which organelle is the principal source of ATP
generated through oxidative phosphorylation?
A. Lysosome
B. Mitochondrion
C. Golgi apparatus
D. Ribosome
Correct Answer: B. Mitochondrion
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 examines a normal human somatic cell and asks where
most of the cell's genomic DNA is located. Which structure contains the
greatest amount of this DNA?
A. Golgi apparatus
B. Nucleus
C. Lysosome
D. Plasma membrane
Correct Answer: B. Nucleus
,Rationale:
The nucleus contains the vast majority of the cell's genomic DNA
organized into chromosomes. The Golgi apparatus and lysosomes
contain proteins and other cellular components but do not house the
nuclear genome. The plasma membrane contains receptors, lipids, and
transport proteins but essentially no genomic DNA.
Question 2
A normal cell is maintaining its internal environment by regulating ion
concentrations, pH, and protein turnover despite continuous changes in
the extracellular environment. Which term best describes this
property?
A. Homeostasis
B. Metastasis
C. Differentiation
D. Senescence
Correct Answer: A. Homeostasis
Rationale:
Homeostasis refers to the ability of a cell or organism to maintain a
relatively stable internal environment despite external changes.
Differentiation refers to acquisition of specialized cellular
characteristics, whereas senescence is a state of essentially permanent
cell-cycle arrest. Metastasis describes dissemination of malignant cells
and is unrelated to routine cellular regulation.
Question 3
A mutation prevents a cellular protein from being correctly folded in the
endoplasmic reticulum. Which cellular process is most directly
, responsible for identifying and disposing of many such abnormal
proteins?
A. Protein degradation through quality-control pathways
B. DNA replication
C. Exocytosis of intact chromosomes
D. Extracellular matrix synthesis
Correct Answer: A. Protein degradation through quality-control
pathways
Rationale:
Cells use protein-quality-control mechanisms to recognize misfolded or
damaged proteins and target them for degradation, helping preserve
cellular function. DNA replication produces new copies of genetic
material and does not remove misfolded proteins. Exocytosis does not
expel chromosomes, and extracellular matrix synthesis produces
structural proteins outside the cell rather than degrading defective
intracellular proteins.
Question 4
A hepatocyte requires ATP to power ion pumps that maintain its
membrane potential. Which organelle is the principal source of ATP
generated through oxidative phosphorylation?
A. Lysosome
B. Mitochondrion
C. Golgi apparatus
D. Ribosome
Correct Answer: B. Mitochondrion
