NR507 | NR507 Advanced Pathophysiology
Midterm v2 | Questions with Correct Answers and
Expert Explanation for Each Question |
Chamberlain
1. Which cellular adaptation is characterized by a decrease in cell size and functional
capacity?
A. Atrophy
B. Hypertrophy
C. Metaplasia
D. Hyperplasia
Correct Answer: A
Expert Explanation: Atrophy occurs when cells shrink in size due to a decrease in
workload, use, or blood supply. This process involves the loss of cell substance and
structural components to conserve energy. It is commonly seen in skeletal muscle during
prolonged immobilization or denervation.
2. Which hormone is primarily responsible for the regulation of sodium balance in the body?
A. Aldosterone
B. Antidiuretic hormone (ADH)
C. Cortisol
D. Oxytocin
Correct Answer: A
Expert Explanation: Aldosterone is a mineralocorticoid secreted by the adrenal cortex
that acts on the distal tubules of the kidneys to promote sodium reabsorption. By retaining
sodium, the body also retains water, which helps regulate blood pressure and volume. This
hormone is a key component of the renin-angiotensin-aldosterone system (RAAS).
3. In the context of acid-base balance, what is the primary compensation mechanism for
respiratory acidosis?
A. Hyperventilation to blow off CO2
B. Decreased renal excretion of H+
C. Increased renal reabsorption of HCO3-
D. Hypoventilation to retain CO2
,Correct Answer: C
Expert Explanation: Respiratory acidosis is characterized by an excess of CO2 due to
hypoventilation. The kidneys compensate by increasing the reabsorption of bicarbonate
(HCO3-) and increasing the secretion of hydrogen ions into the urine. This metabolic
compensation is a slow process that typically takes several days to achieve maximum
effectiveness.
4. Which type of hypersensitivity reaction is mediated by IgE and involves the release of
histamine from mast cells?
A. Type I
B. Type II
C. Type III
D. Type IV
Correct Answer: A
Expert Explanation: Type I hypersensitivity reactions are immediate allergic reactions
triggered by the cross-linking of IgE antibodies on mast cells. This interaction causes
degranulation and the release of inflammatory mediators like histamine and leukotrienes.
Examples include allergic rhinitis, asthma, and systemic anaphylaxis.
5. What is the primary pathophysiology of Type 1 Diabetes Mellitus?
A. Insulin resistance in peripheral tissues
B. Excessive glucagon secretion from alpha cells
C. Inadequate dietary intake of glucose
D. Autoimmune destruction of pancreatic beta cells
Correct Answer: D
Expert Explanation: Type 1 Diabetes Mellitus results from an autoimmune process where
the body’s immune system attacks and destroys insulin-producing beta cells in the Islets of
Langerhans. This leads to an absolute insulin deficiency, requiring exogenous insulin for
survival. Genetic predisposition and environmental triggers are thought to play significant
roles in its development.
6. Which electrolyte imbalance is most commonly associated with a prolonged QT interval on
an EKG?
A. Hyperkalemia
B. Hypernatremia
C. Hypocalcemia
, D. Hypomagnesemia
Correct Answer: C
Expert Explanation: Hypocalcemia slows the process of ventricular repolarization, which
manifests as a prolonged QT interval on an electrocardiogram. This condition increases the
risk of developing life-threatening ventricular arrhythmias such as Torsades de Pointes.
Maintaining normal serum calcium levels is critical for proper cardiac electrical conduction.
7. Metaplasia is best described as:
A. Disordered cell growth and maturation
B. An increase in the total number of cells
C. The replacement of one mature cell type by another
D. Programmed cell death
Correct Answer: C
Expert Explanation: Metaplasia is a reversible change in which one adult cell type is
replaced by another adult cell type better suited to handle a specific stress. A classic
example is the change of ciliated columnar epithelium to squamous epithelium in the
airways of chronic smokers. While adaptive, this change often results in the loss of
important functional mechanisms like mucus secretion.
8. Which substance acts as an endogenous pyrogen to induce fever during inflammation?
A. Interleukin-1 (IL-1)
B. Albumin
C. Serotonin
D. Hemoglobin
Correct Answer: A
Expert Explanation: Interleukin-1 (IL-1) is a primary cytokine released by macrophages
that acts on the hypothalamus to reset the body’s thermostat. This results in an increase in
core body temperature, which is a hallmark of the systemic inflammatory response. Other
cytokines like TNF-alpha and IL-6 also contribute to this pyrogenic effect.
9. What is the hallmark clinical manifestation of Nephrotic Syndrome?
A. Massive proteinuria (>3.5g/day)
B. Gross hematuria
C. High blood pressure
D. Hypolipidemia
Midterm v2 | Questions with Correct Answers and
Expert Explanation for Each Question |
Chamberlain
1. Which cellular adaptation is characterized by a decrease in cell size and functional
capacity?
A. Atrophy
B. Hypertrophy
C. Metaplasia
D. Hyperplasia
Correct Answer: A
Expert Explanation: Atrophy occurs when cells shrink in size due to a decrease in
workload, use, or blood supply. This process involves the loss of cell substance and
structural components to conserve energy. It is commonly seen in skeletal muscle during
prolonged immobilization or denervation.
2. Which hormone is primarily responsible for the regulation of sodium balance in the body?
A. Aldosterone
B. Antidiuretic hormone (ADH)
C. Cortisol
D. Oxytocin
Correct Answer: A
Expert Explanation: Aldosterone is a mineralocorticoid secreted by the adrenal cortex
that acts on the distal tubules of the kidneys to promote sodium reabsorption. By retaining
sodium, the body also retains water, which helps regulate blood pressure and volume. This
hormone is a key component of the renin-angiotensin-aldosterone system (RAAS).
3. In the context of acid-base balance, what is the primary compensation mechanism for
respiratory acidosis?
A. Hyperventilation to blow off CO2
B. Decreased renal excretion of H+
C. Increased renal reabsorption of HCO3-
D. Hypoventilation to retain CO2
,Correct Answer: C
Expert Explanation: Respiratory acidosis is characterized by an excess of CO2 due to
hypoventilation. The kidneys compensate by increasing the reabsorption of bicarbonate
(HCO3-) and increasing the secretion of hydrogen ions into the urine. This metabolic
compensation is a slow process that typically takes several days to achieve maximum
effectiveness.
4. Which type of hypersensitivity reaction is mediated by IgE and involves the release of
histamine from mast cells?
A. Type I
B. Type II
C. Type III
D. Type IV
Correct Answer: A
Expert Explanation: Type I hypersensitivity reactions are immediate allergic reactions
triggered by the cross-linking of IgE antibodies on mast cells. This interaction causes
degranulation and the release of inflammatory mediators like histamine and leukotrienes.
Examples include allergic rhinitis, asthma, and systemic anaphylaxis.
5. What is the primary pathophysiology of Type 1 Diabetes Mellitus?
A. Insulin resistance in peripheral tissues
B. Excessive glucagon secretion from alpha cells
C. Inadequate dietary intake of glucose
D. Autoimmune destruction of pancreatic beta cells
Correct Answer: D
Expert Explanation: Type 1 Diabetes Mellitus results from an autoimmune process where
the body’s immune system attacks and destroys insulin-producing beta cells in the Islets of
Langerhans. This leads to an absolute insulin deficiency, requiring exogenous insulin for
survival. Genetic predisposition and environmental triggers are thought to play significant
roles in its development.
6. Which electrolyte imbalance is most commonly associated with a prolonged QT interval on
an EKG?
A. Hyperkalemia
B. Hypernatremia
C. Hypocalcemia
, D. Hypomagnesemia
Correct Answer: C
Expert Explanation: Hypocalcemia slows the process of ventricular repolarization, which
manifests as a prolonged QT interval on an electrocardiogram. This condition increases the
risk of developing life-threatening ventricular arrhythmias such as Torsades de Pointes.
Maintaining normal serum calcium levels is critical for proper cardiac electrical conduction.
7. Metaplasia is best described as:
A. Disordered cell growth and maturation
B. An increase in the total number of cells
C. The replacement of one mature cell type by another
D. Programmed cell death
Correct Answer: C
Expert Explanation: Metaplasia is a reversible change in which one adult cell type is
replaced by another adult cell type better suited to handle a specific stress. A classic
example is the change of ciliated columnar epithelium to squamous epithelium in the
airways of chronic smokers. While adaptive, this change often results in the loss of
important functional mechanisms like mucus secretion.
8. Which substance acts as an endogenous pyrogen to induce fever during inflammation?
A. Interleukin-1 (IL-1)
B. Albumin
C. Serotonin
D. Hemoglobin
Correct Answer: A
Expert Explanation: Interleukin-1 (IL-1) is a primary cytokine released by macrophages
that acts on the hypothalamus to reset the body’s thermostat. This results in an increase in
core body temperature, which is a hallmark of the systemic inflammatory response. Other
cytokines like TNF-alpha and IL-6 also contribute to this pyrogenic effect.
9. What is the hallmark clinical manifestation of Nephrotic Syndrome?
A. Massive proteinuria (>3.5g/day)
B. Gross hematuria
C. High blood pressure
D. Hypolipidemia
