SCI 225 PATHOPHYSIOLOGY
MIDTERM EXAM
Nightingale College | 2026/2027 Academic Year
Name: ________________ Date: ________________ Score: ______ / 50
Total Questions: 50 | Time: 120 minutes | Passing Score: 80% (40/50)
Instructions: Choose the single best answer unless otherwise indicated.
Section 1 Section 2 Section 3 Section 4 Section 5
Points 20% 25% 20% 20% 15%
Score
EXAM STRUCTURE
Section 1 | CELLULAR INJURY, ADAPTATION & INFLAMMATION | Q1 – Q10
Section 2 | GENETICS, IMMUNITY & IMMUNE DISORDERS | Q11 – Q20
Section 3 | FLUID, ELECTROLYTE & ACID-BASE BALANCE | Q21 – Q30
Section 4 | CARDIOVASCULAR, RESPIRATORY & RENAL PATHOPHYSIOLOGY | Q31 – Q40
Section 5 | NEOPLASIA, ENDOCRINE DISORDERS & NGN-STYLE CASE ANALYSIS | Q41 – Q50
Instructions: Choose the single best answer. Pass: 40 in 120 minutes.
Question 1 of 50
A 58-year-old man with a history of chronic alcohol use presents with upper abdominal pain, nausea, and elevated
serum lipase. A liver biopsy reveals hepatocytes that are markedly enlarged with pale, swollen cytoplasm but
intact nuclear membranes. The pathologist notes that these cellular changes are reversible if the patient abstains
from alcohol. The swelling of these hepatocytes is most directly caused by which mechanism?
A. Accumulation of triglycerides within the cytoplasm due to impaired protein synthesis
B. Failure of ATP-dependent sodium-potassium pumps leading to intracellular sodium and water retention
C. Increased permeability of the mitochondrial membrane causing calcium influx
D. Activation of caspase enzymes that degrade cytoskeletal structural proteins
Correct Answer: B
Rationale: Reversible cellular injury is characterized by cellular swelling caused by failure of ATP-dependent sodium-
potassium pumps, which allows sodium to accumulate intracellularly and draws water into the cell, producing the
classic hydropic degeneration seen here. Triglyceride accumulation (fatty change) is a separate form of reversible
injury and does not directly cause the cellular swelling described in this biopsy.
1
,Question 2 of 50
A 72-year-old woman is admitted with gangrenous changes in her left great toe following untreated peripheral
arterial disease. The tissue is black, shriveled, and demarcated from surrounding skin. Her vital signs are stable,
and laboratory results show a normal white blood cell count. The necrotic process occurring in this toe differs
from liquefactive necrosis in which way?
A. It retains the original tissue architecture despite cell death
B. It is caused by an inflammatory response to pyogenic bacterial infection
C. It involves complete enzymatic dissolution of dead tissue into a liquid
D. It triggers a robust neutrophilic infiltration at the site of necrosis
Correct Answer: A
Rationale: Coagulative necrosis, seen in dry gangrene from ischemic injury, preserves the basic outline of the dead
cells because the denatured structural proteins are not immediately digested by enzymes. Liquefactive necrosis, by
contrast, involves rapid enzymatic dissolution of tissue into a liquid pus, typically driven by neutrophil-derived enzymes
in bacterial infections.
Question 3 of 50
A 45-year-old smoker with a 30-pack-year history presents with a chronic productive cough. Bronchial biopsy
shows stratified squamous epithelium replacing the normal ciliated columnar epithelium in the large airways. The
patient asks the nurse what this change means for his long-term health. The pathophysiologic term for this cellular
adaptation and its clinical significance is best described as:
A. Dysplasia, which is a precancerous change that indicates malignant transformation has begun
B. Metaplasia, which is a reversible replacement of one mature cell type by another in response to chronic
irritation
C. Hyperplasia, which represents an increase in the number of normal cells to meet increased functional demand
D. Anaplasia, which reflects the loss of cellular differentiation characteristic of invasive carcinoma
Correct Answer: B
Rationale: Metaplasia is a reversible adaptive response where one mature cell type is replaced by another, such as
squamous metaplasia of respiratory epithelium from chronic tobacco exposure. Dysplasia is a separate, more
concerning process involving atypical cell growth that is considered precancerous, and should not be confused with the
protective adaptive change seen here.
Question 4 of 50
A 28-year-old woman arrives at the emergency department with urticaria, angioedema, and stridor within minutes
of receiving a bee-sting. Her blood pressure drops to 78/50 mmHg and her heart rate rises to 128 bpm. The nurse
recognizes that the massive histamine release driving this reaction primarily acts through which pathophysiologic
mechanism?
A. Stimulation of T-cell mediated cytotoxicity against the invading allergen
B. Activation of the classical complement pathway through antigen-antibody complexes
C. Binding to H1 and H2 receptors causing widespread vasodilation and increased vascular permeability
D. Direct activation of the coagulation cascade leading to disseminated intravascular coagulation
Correct Answer: C
2
, Rationale: Histamine binds to H1 receptors on endothelial cells and H2 receptors on vascular smooth muscle, causing
vasodilation and increased capillary permeability that produces the urticaria, angioedema, and hypotension seen in
anaphylaxis. Complement activation does occur in some hypersensitivity reactions but is not the primary mechanism in
this IgE-mediated immediate response.
Question 5 of 50
A 65-year-old man undergoes a below-the-knee amputation after a traumatic injury. The surgeon notes that the
necrotic tissue in the distal stump has a foul odor, appears brownish-black, and is spreading along fascial planes.
What is the most likely diagnosis, and which microorganism is most commonly implicated?
A. Dry gangrene caused by gradual arterial occlusion from atherosclerosis
B. Wet gangrene caused by Clostridium perfringens producing gas and toxin-mediated tissue destruction
C. Liquefactive necrosis caused by Staphylococcus aureus forming an abscess cavity
D. Caseous necrosis caused by Mycobacterium tuberculosis forming granulomas in the extremity
Correct Answer: B
Rationale: Wet gangrene is characterized by tissue that is dark, malodorous, and spreading along fascial planes,
typically caused by bacterial superinfection of previously ischemic tissue; Clostridium perfringens is classically
associated with gas gangrene producing crepitus and toxin-mediated destruction. Dry gangrene develops slowly from
arterial insufficiency without bacterial superinfection and appears shriveled rather than spreading.
Question 6 of 50
A pathologist examines a tissue specimen from a patient who died of a myocardial infarction and observes cells
with shrunken, eosinophilic cytoplasm and nuclear pyknosis, karyorrhexis, and karyolysis. No inflammatory
infiltrate is seen at the margins of the infarct during the first 12 hours. The absence of a visible inflammatory
response in the earliest phase of this injury is best explained by which principle?
A. Apoptotic cell death does not elicit inflammation because the cell membrane remains intact
B. The necrotic cells have not yet released damage-associated molecular patterns to attract leukocytes
C. The ischemic tissue environment prevents neutrophil chemotaxis due to low oxygen tension
D. The complement cascade has not been activated because antibodies are absent in the infarct core
Correct Answer: B
Rationale: In the first few hours after ischemic necrosis, the dead cells have not yet released intracellular damage-
associated molecular patterns (DAMPs) such as HMGB1 and mitochondrial DNA that serve as danger signals to
recruit neutrophils and macrophages to the site. Apoptosis is incorrect because the findings (nuclear pyknosis,
eosinophilic cytoplasm) describe coagulative necrosis, not programmed cell death.
Question 7 of 50
A research study demonstrates that prostaglandin E2 levels rise significantly during the early phases of acute
inflammation. A nursing student asks the instructor how prostaglandins contribute to the inflammatory response.
The most accurate response is that prostaglandins:
A. Directly cause vasodilation and increase vascular permeability during the immediate vascular phase
B. Act on the hypothalamus to raise the body temperature set point, producing fever
C. Promote phagocytosis by coating bacterial surfaces for enhanced macrophage recognition
D. Stimulate the proliferation of fibroblasts and angiogenesis during the resolution phase
3
MIDTERM EXAM
Nightingale College | 2026/2027 Academic Year
Name: ________________ Date: ________________ Score: ______ / 50
Total Questions: 50 | Time: 120 minutes | Passing Score: 80% (40/50)
Instructions: Choose the single best answer unless otherwise indicated.
Section 1 Section 2 Section 3 Section 4 Section 5
Points 20% 25% 20% 20% 15%
Score
EXAM STRUCTURE
Section 1 | CELLULAR INJURY, ADAPTATION & INFLAMMATION | Q1 – Q10
Section 2 | GENETICS, IMMUNITY & IMMUNE DISORDERS | Q11 – Q20
Section 3 | FLUID, ELECTROLYTE & ACID-BASE BALANCE | Q21 – Q30
Section 4 | CARDIOVASCULAR, RESPIRATORY & RENAL PATHOPHYSIOLOGY | Q31 – Q40
Section 5 | NEOPLASIA, ENDOCRINE DISORDERS & NGN-STYLE CASE ANALYSIS | Q41 – Q50
Instructions: Choose the single best answer. Pass: 40 in 120 minutes.
Question 1 of 50
A 58-year-old man with a history of chronic alcohol use presents with upper abdominal pain, nausea, and elevated
serum lipase. A liver biopsy reveals hepatocytes that are markedly enlarged with pale, swollen cytoplasm but
intact nuclear membranes. The pathologist notes that these cellular changes are reversible if the patient abstains
from alcohol. The swelling of these hepatocytes is most directly caused by which mechanism?
A. Accumulation of triglycerides within the cytoplasm due to impaired protein synthesis
B. Failure of ATP-dependent sodium-potassium pumps leading to intracellular sodium and water retention
C. Increased permeability of the mitochondrial membrane causing calcium influx
D. Activation of caspase enzymes that degrade cytoskeletal structural proteins
Correct Answer: B
Rationale: Reversible cellular injury is characterized by cellular swelling caused by failure of ATP-dependent sodium-
potassium pumps, which allows sodium to accumulate intracellularly and draws water into the cell, producing the
classic hydropic degeneration seen here. Triglyceride accumulation (fatty change) is a separate form of reversible
injury and does not directly cause the cellular swelling described in this biopsy.
1
,Question 2 of 50
A 72-year-old woman is admitted with gangrenous changes in her left great toe following untreated peripheral
arterial disease. The tissue is black, shriveled, and demarcated from surrounding skin. Her vital signs are stable,
and laboratory results show a normal white blood cell count. The necrotic process occurring in this toe differs
from liquefactive necrosis in which way?
A. It retains the original tissue architecture despite cell death
B. It is caused by an inflammatory response to pyogenic bacterial infection
C. It involves complete enzymatic dissolution of dead tissue into a liquid
D. It triggers a robust neutrophilic infiltration at the site of necrosis
Correct Answer: A
Rationale: Coagulative necrosis, seen in dry gangrene from ischemic injury, preserves the basic outline of the dead
cells because the denatured structural proteins are not immediately digested by enzymes. Liquefactive necrosis, by
contrast, involves rapid enzymatic dissolution of tissue into a liquid pus, typically driven by neutrophil-derived enzymes
in bacterial infections.
Question 3 of 50
A 45-year-old smoker with a 30-pack-year history presents with a chronic productive cough. Bronchial biopsy
shows stratified squamous epithelium replacing the normal ciliated columnar epithelium in the large airways. The
patient asks the nurse what this change means for his long-term health. The pathophysiologic term for this cellular
adaptation and its clinical significance is best described as:
A. Dysplasia, which is a precancerous change that indicates malignant transformation has begun
B. Metaplasia, which is a reversible replacement of one mature cell type by another in response to chronic
irritation
C. Hyperplasia, which represents an increase in the number of normal cells to meet increased functional demand
D. Anaplasia, which reflects the loss of cellular differentiation characteristic of invasive carcinoma
Correct Answer: B
Rationale: Metaplasia is a reversible adaptive response where one mature cell type is replaced by another, such as
squamous metaplasia of respiratory epithelium from chronic tobacco exposure. Dysplasia is a separate, more
concerning process involving atypical cell growth that is considered precancerous, and should not be confused with the
protective adaptive change seen here.
Question 4 of 50
A 28-year-old woman arrives at the emergency department with urticaria, angioedema, and stridor within minutes
of receiving a bee-sting. Her blood pressure drops to 78/50 mmHg and her heart rate rises to 128 bpm. The nurse
recognizes that the massive histamine release driving this reaction primarily acts through which pathophysiologic
mechanism?
A. Stimulation of T-cell mediated cytotoxicity against the invading allergen
B. Activation of the classical complement pathway through antigen-antibody complexes
C. Binding to H1 and H2 receptors causing widespread vasodilation and increased vascular permeability
D. Direct activation of the coagulation cascade leading to disseminated intravascular coagulation
Correct Answer: C
2
, Rationale: Histamine binds to H1 receptors on endothelial cells and H2 receptors on vascular smooth muscle, causing
vasodilation and increased capillary permeability that produces the urticaria, angioedema, and hypotension seen in
anaphylaxis. Complement activation does occur in some hypersensitivity reactions but is not the primary mechanism in
this IgE-mediated immediate response.
Question 5 of 50
A 65-year-old man undergoes a below-the-knee amputation after a traumatic injury. The surgeon notes that the
necrotic tissue in the distal stump has a foul odor, appears brownish-black, and is spreading along fascial planes.
What is the most likely diagnosis, and which microorganism is most commonly implicated?
A. Dry gangrene caused by gradual arterial occlusion from atherosclerosis
B. Wet gangrene caused by Clostridium perfringens producing gas and toxin-mediated tissue destruction
C. Liquefactive necrosis caused by Staphylococcus aureus forming an abscess cavity
D. Caseous necrosis caused by Mycobacterium tuberculosis forming granulomas in the extremity
Correct Answer: B
Rationale: Wet gangrene is characterized by tissue that is dark, malodorous, and spreading along fascial planes,
typically caused by bacterial superinfection of previously ischemic tissue; Clostridium perfringens is classically
associated with gas gangrene producing crepitus and toxin-mediated destruction. Dry gangrene develops slowly from
arterial insufficiency without bacterial superinfection and appears shriveled rather than spreading.
Question 6 of 50
A pathologist examines a tissue specimen from a patient who died of a myocardial infarction and observes cells
with shrunken, eosinophilic cytoplasm and nuclear pyknosis, karyorrhexis, and karyolysis. No inflammatory
infiltrate is seen at the margins of the infarct during the first 12 hours. The absence of a visible inflammatory
response in the earliest phase of this injury is best explained by which principle?
A. Apoptotic cell death does not elicit inflammation because the cell membrane remains intact
B. The necrotic cells have not yet released damage-associated molecular patterns to attract leukocytes
C. The ischemic tissue environment prevents neutrophil chemotaxis due to low oxygen tension
D. The complement cascade has not been activated because antibodies are absent in the infarct core
Correct Answer: B
Rationale: In the first few hours after ischemic necrosis, the dead cells have not yet released intracellular damage-
associated molecular patterns (DAMPs) such as HMGB1 and mitochondrial DNA that serve as danger signals to
recruit neutrophils and macrophages to the site. Apoptosis is incorrect because the findings (nuclear pyknosis,
eosinophilic cytoplasm) describe coagulative necrosis, not programmed cell death.
Question 7 of 50
A research study demonstrates that prostaglandin E2 levels rise significantly during the early phases of acute
inflammation. A nursing student asks the instructor how prostaglandins contribute to the inflammatory response.
The most accurate response is that prostaglandins:
A. Directly cause vasodilation and increase vascular permeability during the immediate vascular phase
B. Act on the hypothalamus to raise the body temperature set point, producing fever
C. Promote phagocytosis by coating bacterial surfaces for enhanced macrophage recognition
D. Stimulate the proliferation of fibroblasts and angiogenesis during the resolution phase
3
