HSC 4555 Exam 1 V1 | HSC 4555 Pathophysiology 1 | Actual Q&A with
Rationale (HSC4555 Exam 1) | University of Central Florida
1. A 55-year-old male with a history of chronic smoking presents with a cough. A biopsy of his
bronchial epithelium reveals that the normal ciliated columnar cells have been replaced by
stratified squamous cells. What is the most likely cellular adaptation?
A. Metaplasia
B. Hypertrophy
C. Dysplasia
D. Atrophy
Answer: A
Explanation: Metaplasia is the reversible replacement of one mature cell type by another
mature cell type, often as an adaptive response to chronic irritation. In smokers, the fragile
columnar cells are replaced by tougher squamous cells to withstand the smoke. While this
provides protection, the loss of cilia impairs the ability to clear mucus and debris from the
lungs.
2. Following an intense weightlifting program, a 22-year-old athlete experiences an increase
in the size of his skeletal muscle cells. This process is known as:
A. Dysplasia
B. Hyperplasia
C. Metaplasia
D. Hypertrophy
Answer: D
Explanation: Hypertrophy refers to an increase in the size of cells, which leads to an
increase in the size of the affected organ. In skeletal muscles, this occurs because the cells
cannot divide to accommodate increased mechanical demand. This is a physiologic
response to exercise but can also occur pathologically, such as in the heart due to
hypertension.
3. During a programmed cell death process, a cell shrinks and its DNA fragments without
inducing an inflammatory response. This process is best described as:
A. Apoptosis
B. Autophagy
C. Necrosis
,D. Karyolysis
Answer: A
Explanation: Apoptosis is a regulated, energy-dependent process of programmed cell
death that eliminates unwanted or damaged cells. Unlike necrosis, it does not cause the cell
to swell and burst, thereby avoiding the release of intracellular contents that trigger
inflammation. It plays a critical role in embryonic development and the maintenance of
tissue homeostasis by balancing cell proliferation.
4. A patient suffers a myocardial infarction resulting in the death of cardiac tissue due to a
lack of oxygen. The cellular death characterized by the denaturing of proteins and
maintaining the tissue architecture for several days is:
A. Liquefactive necrosis
B. Caseous necrosis
C. Fat necrosis
D. Coagulative necrosis
Answer: D
Explanation: Coagulative necrosis typically occurs in solid organs like the heart, kidneys,
and adrenal glands following hypoxia or ischemia. The process involves protein
denaturation, which prevents the cell from digesting itself, thus preserving the tissue
structure for a short period. Eventually, leukocytes arrive to phagocytize the dead cells and
replace them with scar tissue.
5. Which of the following is the most common cause of cellular injury in clinical practice?
A. Genetic defects
B. Hypoxia
C. Nutritional imbalances
D. Chemical agents
Answer: B
Explanation: Hypoxia, or a lack of sufficient oxygen, is the most common cause of cellular
injury leading to cellular death. It can result from reduced oxygen in the atmosphere, loss
of hemoglobin, or decreased blood flow (ischemia). Without oxygen, the cell cannot
produce ATP, leading to the failure of the sodium-potassium pump and subsequent cellular
swelling.
6. Which hormone is primarily responsible for the regulation of water balance by increasing
the permeability of the collecting ducts in the kidney?
A. Antidiuretic hormone (ADH)
, B. Aldosterone
C. Atrial natriuretic peptide (ANP)
D. Renin
Answer: A
Explanation: Antidiuretic hormone, also known as vasopressin, is secreted by the
posterior pituitary in response to high plasma osmolality or low blood volume. It acts on
the kidneys to increase water reabsorption, which dilutes the plasma and increases blood
volume. A deficiency in ADH leads to diabetes insipidus, characterized by the excretion of
large volumes of dilute urine.
7. A patient presents with a serum potassium level of 6.5 mEq/L. Which clinical manifestation
is a priority concern for this patient?
A. Muscle wasting
B. Cardiac dysrhythmias
C. Polyuria
D. Increased hunger
Answer: B
Explanation: Hyperkalemia, defined as a potassium level above 5.0 mEq/L, is a medical
emergency because it affects the resting membrane potential of cardiac cells. High
potassium levels can lead to peaked T waves, widened QRS complexes, and potentially fatal
ventricular fibrillation or asystole. Immediate intervention is often required to shift
potassium back into the cells or remove it from the body.
8. An arterial blood gas (ABG) report shows pH 7.25, PaCO2 55 mmHg, and HCO3 24 mEq/L.
This patient is experiencing:
A. Metabolic Acidosis
B. Respiratory Alkalosis
C. Respiratory Acidosis
D. Metabolic Alkalosis
Answer: C
Explanation: Respiratory acidosis is characterized by a low pH (below 7.35) and an
elevated PaCO2 (above 45 mmHg), indicating alveolar hypoventilation. In this case, the
bicarbonate (HCO3) is within the normal range, suggesting that the kidneys have not yet
compensated for the respiratory issue. This condition is commonly seen in patients with
COPD, pneumonia, or respiratory depression from sedation.
Rationale (HSC4555 Exam 1) | University of Central Florida
1. A 55-year-old male with a history of chronic smoking presents with a cough. A biopsy of his
bronchial epithelium reveals that the normal ciliated columnar cells have been replaced by
stratified squamous cells. What is the most likely cellular adaptation?
A. Metaplasia
B. Hypertrophy
C. Dysplasia
D. Atrophy
Answer: A
Explanation: Metaplasia is the reversible replacement of one mature cell type by another
mature cell type, often as an adaptive response to chronic irritation. In smokers, the fragile
columnar cells are replaced by tougher squamous cells to withstand the smoke. While this
provides protection, the loss of cilia impairs the ability to clear mucus and debris from the
lungs.
2. Following an intense weightlifting program, a 22-year-old athlete experiences an increase
in the size of his skeletal muscle cells. This process is known as:
A. Dysplasia
B. Hyperplasia
C. Metaplasia
D. Hypertrophy
Answer: D
Explanation: Hypertrophy refers to an increase in the size of cells, which leads to an
increase in the size of the affected organ. In skeletal muscles, this occurs because the cells
cannot divide to accommodate increased mechanical demand. This is a physiologic
response to exercise but can also occur pathologically, such as in the heart due to
hypertension.
3. During a programmed cell death process, a cell shrinks and its DNA fragments without
inducing an inflammatory response. This process is best described as:
A. Apoptosis
B. Autophagy
C. Necrosis
,D. Karyolysis
Answer: A
Explanation: Apoptosis is a regulated, energy-dependent process of programmed cell
death that eliminates unwanted or damaged cells. Unlike necrosis, it does not cause the cell
to swell and burst, thereby avoiding the release of intracellular contents that trigger
inflammation. It plays a critical role in embryonic development and the maintenance of
tissue homeostasis by balancing cell proliferation.
4. A patient suffers a myocardial infarction resulting in the death of cardiac tissue due to a
lack of oxygen. The cellular death characterized by the denaturing of proteins and
maintaining the tissue architecture for several days is:
A. Liquefactive necrosis
B. Caseous necrosis
C. Fat necrosis
D. Coagulative necrosis
Answer: D
Explanation: Coagulative necrosis typically occurs in solid organs like the heart, kidneys,
and adrenal glands following hypoxia or ischemia. The process involves protein
denaturation, which prevents the cell from digesting itself, thus preserving the tissue
structure for a short period. Eventually, leukocytes arrive to phagocytize the dead cells and
replace them with scar tissue.
5. Which of the following is the most common cause of cellular injury in clinical practice?
A. Genetic defects
B. Hypoxia
C. Nutritional imbalances
D. Chemical agents
Answer: B
Explanation: Hypoxia, or a lack of sufficient oxygen, is the most common cause of cellular
injury leading to cellular death. It can result from reduced oxygen in the atmosphere, loss
of hemoglobin, or decreased blood flow (ischemia). Without oxygen, the cell cannot
produce ATP, leading to the failure of the sodium-potassium pump and subsequent cellular
swelling.
6. Which hormone is primarily responsible for the regulation of water balance by increasing
the permeability of the collecting ducts in the kidney?
A. Antidiuretic hormone (ADH)
, B. Aldosterone
C. Atrial natriuretic peptide (ANP)
D. Renin
Answer: A
Explanation: Antidiuretic hormone, also known as vasopressin, is secreted by the
posterior pituitary in response to high plasma osmolality or low blood volume. It acts on
the kidneys to increase water reabsorption, which dilutes the plasma and increases blood
volume. A deficiency in ADH leads to diabetes insipidus, characterized by the excretion of
large volumes of dilute urine.
7. A patient presents with a serum potassium level of 6.5 mEq/L. Which clinical manifestation
is a priority concern for this patient?
A. Muscle wasting
B. Cardiac dysrhythmias
C. Polyuria
D. Increased hunger
Answer: B
Explanation: Hyperkalemia, defined as a potassium level above 5.0 mEq/L, is a medical
emergency because it affects the resting membrane potential of cardiac cells. High
potassium levels can lead to peaked T waves, widened QRS complexes, and potentially fatal
ventricular fibrillation or asystole. Immediate intervention is often required to shift
potassium back into the cells or remove it from the body.
8. An arterial blood gas (ABG) report shows pH 7.25, PaCO2 55 mmHg, and HCO3 24 mEq/L.
This patient is experiencing:
A. Metabolic Acidosis
B. Respiratory Alkalosis
C. Respiratory Acidosis
D. Metabolic Alkalosis
Answer: C
Explanation: Respiratory acidosis is characterized by a low pH (below 7.35) and an
elevated PaCO2 (above 45 mmHg), indicating alveolar hypoventilation. In this case, the
bicarbonate (HCO3) is within the normal range, suggesting that the kidneys have not yet
compensated for the respiratory issue. This condition is commonly seen in patients with
COPD, pneumonia, or respiratory depression from sedation.
