NUR 546/NUR546 Exam 1 V1 | Advanced
Pathophysiology Q&A with Rationale |
William Paterson University
1. A patient is diagnosed with muscle atrophy after being in a cast for six weeks. Which
process best describes this cellular adaptation?
A. An increase in cell size due to increased workload
B. A decrease in cell size due to decreased protein synthesis or increased protein
catabolism
C. The replacement of one mature cell type with another
D. An increase in the number of cells within an organ
Answer: B
Rationale: Atrophy is the shrinkage in cellular size caused by a loss of cellular substance.
In the clinical setting of immobilization, it is specifically referred to as disuse atrophy. This
process involves a decrease in protein synthesis and an increase in protein degradation
through the ubiquitin-proteasome pathway.
2. Which of the following describes metaplasia in a chronic smoker?
A. Irreversible change in the shape and organization of cells
B. The replacement of normal columnar ciliated epithelial cells by stratified squamous
epithelial cells
,C. Decrease in the size of the bronchial epithelial cells
D. An increase in the total number of goblet cells
Answer: B
Rationale: Metaplasia is the reversible replacement of one mature cell type by another,
often less differentiated, cell type. In smokers, the fragile ciliated columnar epithelium is
replaced by stratified squamous epithelium to better withstand irritation. However, this
adaptation results in the loss of vital protective mechanisms like mucus secretion and
ciliary clearance.
3. A patient has a serum sodium level of 155 mEq/L. Which of the following clinical
manifestations is most likely?
A. Muscle weakness and bradycardia
B. Confusion, thirst, and dry mucous membranes
C. Abdominal cramping and diarrhea
D. Hyporeflexia and hypotension
Answer: B
Rationale: Hypernatremia occurs when serum sodium levels exceed 145 mEq/L, leading to
hypertonicity of the extracellular fluid. This causes water to shift out of the cells, resulting
in cellular dehydration, especially in the brain. Common symptoms include intense thirst,
restlessness, and central nervous system irritability.
, 4. What is the primary mechanism of cellular injury caused by hypoxia?
A. Increased intracellular calcium levels and activation of enzymes
B. Direct damage to the cell membrane by free radicals
C. Release of histamine from mast cells
D. Decreased ATP production leading to failure of the sodium-potassium pump
Answer: D
Rationale: Hypoxia leads to a reduction in aerobic mitochondrial respiration, which causes
a significant drop in ATP production. Without ATP, the Na+/K+ pump fails, allowing
sodium to enter the cell and water to follow, resulting in cellular swelling. This sequence is
one of the earliest and most critical changes in reversible cell injury.
5. An ECG shows peaked T waves in a patient with chronic kidney disease. Which electrolyte
imbalance is suspected?
A. Hypocalcemia
B. Hyperkalemia
C. Hypermagnesemia
D. Hyponatremia
Answer: B
Rationale: Hyperkalemia, or high serum potassium, is common in kidney disease due to
impaired renal excretion. Tall, peaked T waves are a classic early sign of potassium’s effect
Pathophysiology Q&A with Rationale |
William Paterson University
1. A patient is diagnosed with muscle atrophy after being in a cast for six weeks. Which
process best describes this cellular adaptation?
A. An increase in cell size due to increased workload
B. A decrease in cell size due to decreased protein synthesis or increased protein
catabolism
C. The replacement of one mature cell type with another
D. An increase in the number of cells within an organ
Answer: B
Rationale: Atrophy is the shrinkage in cellular size caused by a loss of cellular substance.
In the clinical setting of immobilization, it is specifically referred to as disuse atrophy. This
process involves a decrease in protein synthesis and an increase in protein degradation
through the ubiquitin-proteasome pathway.
2. Which of the following describes metaplasia in a chronic smoker?
A. Irreversible change in the shape and organization of cells
B. The replacement of normal columnar ciliated epithelial cells by stratified squamous
epithelial cells
,C. Decrease in the size of the bronchial epithelial cells
D. An increase in the total number of goblet cells
Answer: B
Rationale: Metaplasia is the reversible replacement of one mature cell type by another,
often less differentiated, cell type. In smokers, the fragile ciliated columnar epithelium is
replaced by stratified squamous epithelium to better withstand irritation. However, this
adaptation results in the loss of vital protective mechanisms like mucus secretion and
ciliary clearance.
3. A patient has a serum sodium level of 155 mEq/L. Which of the following clinical
manifestations is most likely?
A. Muscle weakness and bradycardia
B. Confusion, thirst, and dry mucous membranes
C. Abdominal cramping and diarrhea
D. Hyporeflexia and hypotension
Answer: B
Rationale: Hypernatremia occurs when serum sodium levels exceed 145 mEq/L, leading to
hypertonicity of the extracellular fluid. This causes water to shift out of the cells, resulting
in cellular dehydration, especially in the brain. Common symptoms include intense thirst,
restlessness, and central nervous system irritability.
, 4. What is the primary mechanism of cellular injury caused by hypoxia?
A. Increased intracellular calcium levels and activation of enzymes
B. Direct damage to the cell membrane by free radicals
C. Release of histamine from mast cells
D. Decreased ATP production leading to failure of the sodium-potassium pump
Answer: D
Rationale: Hypoxia leads to a reduction in aerobic mitochondrial respiration, which causes
a significant drop in ATP production. Without ATP, the Na+/K+ pump fails, allowing
sodium to enter the cell and water to follow, resulting in cellular swelling. This sequence is
one of the earliest and most critical changes in reversible cell injury.
5. An ECG shows peaked T waves in a patient with chronic kidney disease. Which electrolyte
imbalance is suspected?
A. Hypocalcemia
B. Hyperkalemia
C. Hypermagnesemia
D. Hyponatremia
Answer: B
Rationale: Hyperkalemia, or high serum potassium, is common in kidney disease due to
impaired renal excretion. Tall, peaked T waves are a classic early sign of potassium’s effect
