NURS 611 Exam 3: Advanced Pathophysiology
Questions and Verified Answers (Latest 2026/2027) |
Graded A
Section 1: Neurological Pathophysiology
Q1: Which pathophysiological mechanism is primarily
responsible for the tissue damage observed during an ischemic
stroke?
A) Excessive vasoconstriction leading to hypoxia
B) Excitotoxicity mediated by glutamate leading to intracellular
calcium influx
C) Direct compression of neurons by cerebrospinal fluid
D) Immediate apoptosis of glial cells due to glucose deprivation
CORRECT ANSWER>: B) Excitotoxicity mediated by glutamate
leading to intracellular calcium influx.
Rationale: In ischemic stroke, energy failure leads to the failure
of Na+/K+ ATPase pumps. This causes depolarization and
massive release of glutamate, which binds to NMDA receptors,
causing excessive calcium influx into neurons, ultimately leading
to enzymatic destruction and cell death (excitotoxicity).
,Q2: In the context of traumatic brain injury (TBI), what
distinguishes cytotoxic cerebral edema from vasogenic cerebral
edema?
A) Cytotoxic edema involves disruption of the blood-brain
barrier, while vasogenic involves intact capillaries.
B) Cytotoxic edema is caused by an increase in intracellular fluid
due to pump failure, while vasogenic edema is caused by an
increase in extracellular fluid due to blood-brain barrier
disruption.
C) Vasogenic edema occurs primarily in the gray matter, while
cytotoxic occurs in the white matter.
D) Cytotoxic edema is driven by hydrostatic pressure, while
vasogenic is driven by osmotic pressure.
CORRECT ANSWER>: B) Cytotoxic edema is caused by an
increase in intracellular fluid due to pump failure, while
vasogenic edema is caused by an increase in extracellular fluid
due to blood-brain barrier disruption.
Rationale: Cytotoxic edema occurs when ischemia/hypoxia
causes failure of the Na+/K+ ATPase pump, driving sodium (and
water) into the cells. Vasogenic edema occurs when
inflammatory mediators (like bradykinin and histamine) open
tight junctions in the blood-brain barrier, allowing fluid and
proteins to leak into the extracellular space.
,Q3: The pathognomonic neurological finding of Alzheimer’s
disease at the cellular level is the extracellular accumulation of:
A) Alpha-synuclein
B) Tau proteins
C) Amyloid-beta (Aβ) plaques
D) Lewy bodies
CORRECT ANSWER>: C) Amyloid-beta (Aβ) plaques.
Rationale: While intracellular neurofibrillary tangles (composed
of hyperphosphorylated tau) are also a hallmark, the
extracellular accumulation of amyloid-beta plaques is the
primary defining pathological feature associated with amyloid
precursor protein (APP) misprocessing.
Q4: Parkinson’s disease is characterized by the progressive
degeneration of dopaminergic neurons primarily located in
which area of the brain?
A) The caudate nucleus
B) The putamen
C) The substantia nigra pars compacta
D) The globus pallidus
, CORRECT ANSWER>: C) The substantia nigra pars compacta.
Rationale: Parkinson's disease involves the degeneration of
neurons in the substantia nigra pars compacta, which project to
the striatum (caudate and putamen). This depletion of
dopamine disrupts the basal ganglia's ability to modulate the
direct and indirect motor pathways.
Q5: Which immunological mechanism is primarily responsible
for the demyelination seen in Multiple Sclerosis (MS)?
A) Autoantibody destruction of Schwann cells
B) CD4+ T-cell mediated attack against myelin basic protein in
the CNS
C) Complement-mediated lysis of peripheral nerve axons
D) B-cell aplasia leading to viral reactivation
CORRECT ANSWER>: B) CD4+ T-cell mediated attack against
myelin basic protein in the CNS.
Rationale: MS is a T-cell mediated autoimmune disease.
Autoreactive CD4+ Th1 and Th17 cells cross the blood-brain
barrier and recognize myelin antigens (such as myelin basic
protein), triggering an inflammatory cascade that destroys
oligodendrocytes and CNS myelin.
Questions and Verified Answers (Latest 2026/2027) |
Graded A
Section 1: Neurological Pathophysiology
Q1: Which pathophysiological mechanism is primarily
responsible for the tissue damage observed during an ischemic
stroke?
A) Excessive vasoconstriction leading to hypoxia
B) Excitotoxicity mediated by glutamate leading to intracellular
calcium influx
C) Direct compression of neurons by cerebrospinal fluid
D) Immediate apoptosis of glial cells due to glucose deprivation
CORRECT ANSWER>: B) Excitotoxicity mediated by glutamate
leading to intracellular calcium influx.
Rationale: In ischemic stroke, energy failure leads to the failure
of Na+/K+ ATPase pumps. This causes depolarization and
massive release of glutamate, which binds to NMDA receptors,
causing excessive calcium influx into neurons, ultimately leading
to enzymatic destruction and cell death (excitotoxicity).
,Q2: In the context of traumatic brain injury (TBI), what
distinguishes cytotoxic cerebral edema from vasogenic cerebral
edema?
A) Cytotoxic edema involves disruption of the blood-brain
barrier, while vasogenic involves intact capillaries.
B) Cytotoxic edema is caused by an increase in intracellular fluid
due to pump failure, while vasogenic edema is caused by an
increase in extracellular fluid due to blood-brain barrier
disruption.
C) Vasogenic edema occurs primarily in the gray matter, while
cytotoxic occurs in the white matter.
D) Cytotoxic edema is driven by hydrostatic pressure, while
vasogenic is driven by osmotic pressure.
CORRECT ANSWER>: B) Cytotoxic edema is caused by an
increase in intracellular fluid due to pump failure, while
vasogenic edema is caused by an increase in extracellular fluid
due to blood-brain barrier disruption.
Rationale: Cytotoxic edema occurs when ischemia/hypoxia
causes failure of the Na+/K+ ATPase pump, driving sodium (and
water) into the cells. Vasogenic edema occurs when
inflammatory mediators (like bradykinin and histamine) open
tight junctions in the blood-brain barrier, allowing fluid and
proteins to leak into the extracellular space.
,Q3: The pathognomonic neurological finding of Alzheimer’s
disease at the cellular level is the extracellular accumulation of:
A) Alpha-synuclein
B) Tau proteins
C) Amyloid-beta (Aβ) plaques
D) Lewy bodies
CORRECT ANSWER>: C) Amyloid-beta (Aβ) plaques.
Rationale: While intracellular neurofibrillary tangles (composed
of hyperphosphorylated tau) are also a hallmark, the
extracellular accumulation of amyloid-beta plaques is the
primary defining pathological feature associated with amyloid
precursor protein (APP) misprocessing.
Q4: Parkinson’s disease is characterized by the progressive
degeneration of dopaminergic neurons primarily located in
which area of the brain?
A) The caudate nucleus
B) The putamen
C) The substantia nigra pars compacta
D) The globus pallidus
, CORRECT ANSWER>: C) The substantia nigra pars compacta.
Rationale: Parkinson's disease involves the degeneration of
neurons in the substantia nigra pars compacta, which project to
the striatum (caudate and putamen). This depletion of
dopamine disrupts the basal ganglia's ability to modulate the
direct and indirect motor pathways.
Q5: Which immunological mechanism is primarily responsible
for the demyelination seen in Multiple Sclerosis (MS)?
A) Autoantibody destruction of Schwann cells
B) CD4+ T-cell mediated attack against myelin basic protein in
the CNS
C) Complement-mediated lysis of peripheral nerve axons
D) B-cell aplasia leading to viral reactivation
CORRECT ANSWER>: B) CD4+ T-cell mediated attack against
myelin basic protein in the CNS.
Rationale: MS is a T-cell mediated autoimmune disease.
Autoreactive CD4+ Th1 and Th17 cells cross the blood-brain
barrier and recognize myelin antigens (such as myelin basic
protein), triggering an inflammatory cascade that destroys
oligodendrocytes and CNS myelin.
