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 healthy hepatocyte maintains normal structure and function despite
continuous exposure to minor metabolic stresses. Which cellular
feature best allows the cell to preserve homeostasis under these
conditions?
A. Elimination of all reactive oxygen species
B. Continuous replacement and repair of cellular components
C. Permanent activation of stress-response pathways
D. Complete inhibition of cellular metabolism
,Correct Answer: B. Continuous replacement and repair of cellular
components
Rationale:
Cellular health depends on the ability to maintain homeostasis through
ongoing synthesis, repair, degradation, and replacement of cellular
components. Cellular housekeeping processes allow cells to adapt to
routine metabolic demands without progressing to injury. A is incorrect
because some reactive oxygen species are physiologically produced and
used in signaling; C is incorrect because persistent activation of stress
pathways is not required in a healthy cell; D is incorrect because
metabolism is essential for normal cellular function.
Question 2
A mutation occurs in a somatic cell and changes the coding sequence of
a gene. Which cellular component is most directly responsible for
transmitting the altered genetic information to daughter cells during
cell division?
A. Lysosome
B. Ribosome
C. DNA
D. Golgi apparatus
Correct Answer: C. DNA
Rationale:
DNA stores hereditary information and is replicated so that genetic
information can be transmitted to daughter cells. A lysosome degrades
macromolecules, a ribosome synthesizes proteins, and the Golgi
, apparatus modifies and sorts proteins, so none directly serves as the
genetic information repository.
Question 3
A cell contains damaged proteins that must be removed to maintain
normal cellular function. Which system is primarily responsible for
selective degradation of many intracellular proteins?
A. Proteasome
B. Nucleolus
C. Mitochondrial matrix
D. Smooth endoplasmic reticulum
Correct Answer: A. Proteasome
Rationale:
The ubiquitin-proteasome system selectively targets many intracellular
proteins for degradation, helping maintain protein quality and cellular
housekeeping. The nucleolus participates in ribosomal RNA production,
the mitochondrial matrix contains enzymes involved in oxidative
metabolism, and the smooth endoplasmic reticulum is involved in lipid
metabolism and other functions rather than serving as the primary
intracellular protein-degradation system.
Question 4
A patient develops severe hypoxia during an episode of shock. Which
cellular process is expected to decrease first as mitochondrial oxidative
phosphorylation becomes impaired?
A. ATP production
B. DNA replication
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 healthy hepatocyte maintains normal structure and function despite
continuous exposure to minor metabolic stresses. Which cellular
feature best allows the cell to preserve homeostasis under these
conditions?
A. Elimination of all reactive oxygen species
B. Continuous replacement and repair of cellular components
C. Permanent activation of stress-response pathways
D. Complete inhibition of cellular metabolism
,Correct Answer: B. Continuous replacement and repair of cellular
components
Rationale:
Cellular health depends on the ability to maintain homeostasis through
ongoing synthesis, repair, degradation, and replacement of cellular
components. Cellular housekeeping processes allow cells to adapt to
routine metabolic demands without progressing to injury. A is incorrect
because some reactive oxygen species are physiologically produced and
used in signaling; C is incorrect because persistent activation of stress
pathways is not required in a healthy cell; D is incorrect because
metabolism is essential for normal cellular function.
Question 2
A mutation occurs in a somatic cell and changes the coding sequence of
a gene. Which cellular component is most directly responsible for
transmitting the altered genetic information to daughter cells during
cell division?
A. Lysosome
B. Ribosome
C. DNA
D. Golgi apparatus
Correct Answer: C. DNA
Rationale:
DNA stores hereditary information and is replicated so that genetic
information can be transmitted to daughter cells. A lysosome degrades
macromolecules, a ribosome synthesizes proteins, and the Golgi
, apparatus modifies and sorts proteins, so none directly serves as the
genetic information repository.
Question 3
A cell contains damaged proteins that must be removed to maintain
normal cellular function. Which system is primarily responsible for
selective degradation of many intracellular proteins?
A. Proteasome
B. Nucleolus
C. Mitochondrial matrix
D. Smooth endoplasmic reticulum
Correct Answer: A. Proteasome
Rationale:
The ubiquitin-proteasome system selectively targets many intracellular
proteins for degradation, helping maintain protein quality and cellular
housekeeping. The nucleolus participates in ribosomal RNA production,
the mitochondrial matrix contains enzymes involved in oxidative
metabolism, and the smooth endoplasmic reticulum is involved in lipid
metabolism and other functions rather than serving as the primary
intracellular protein-degradation system.
Question 4
A patient develops severe hypoxia during an episode of shock. Which
cellular process is expected to decrease first as mitochondrial oxidative
phosphorylation becomes impaired?
A. ATP production
B. DNA replication
