Week 1 Knowledge Checks | South University
1. A 68-year-old patient with chronic obstructive pulmonary disease has an enlarged right ventricle
due to chronic hypoxemia. Which cellular adaptation does this represent?
A) Hyperplasia
B) Hypertrophy
C) Metaplasia
D) Atrophy
Correct Answer: Hypertrophy
Rationale: Hypertrophy is an increase in cell size that occurs in tissues incapable of cell division, such
as cardiac muscle. The right ventricle enlarges because individual myocardial cells increase in size in
response to increased workload from chronic hypoxemia. Hyperplasia involves an increase in cell
number and does not occur in cardiac muscle. Metaplasia is the replacement of one cell type by
another, and atrophy is a decrease in cell size.
2. Which of the following best describes the primary function of the sodium-potassium pump in
maintaining cellular homeostasis?
A) Facilitating glucose diffusion into the cell
B) Maintaining high intracellular potassium and low intracellular sodium concentrations
C) Pumping calcium into the sarcoplasmic reticulum
D) Depolarizing the cell membrane during action potentials
Correct Answer: Maintaining high intracellular potassium and low intracellular sodium concentrations
Rationale: The ATP-dependent sodium-potassium pump transports three sodium ions out of the cell
and two potassium ions into the cell, maintaining high intracellular potassium and low intracellular
sodium concentrations. This electrochemical gradient is essential for resting membrane potential,
nutrient transport, and cell volume regulation. Glucose diffusion occurs through separate
transporters, calcium sequestration is performed by the sarcoplasmic reticulum, and depolarization
involves sodium channel opening.
,3. A pathologist examines a bronchial biopsy from a long-term smoker and notes that the normal
ciliated columnar epithelium has been replaced by stratified squamous epithelium. Which cellular
adaptation does this finding represent?
A) Dysplasia
B) Hyperplasia
C) Metaplasia
D) Anaplasia
Correct Answer: Metaplasia
Rationale: Metaplasia is the reversible replacement of one mature cell type by another, often less
specialized, cell type in response to chronic irritation. In smokers, ciliated columnar epithelium is
replaced by stratified squamous epithelium, which is more resistant to irritation but loses cilia and
mucus clearance function. Dysplasia involves disordered growth with atypical cells, hyperplasia is an
increase in cell number, and anaplasia refers to a loss of cellular differentiation.
4. A 55-year-old woman with a history of chronic hypertension has an echocardiogram showing
thickening of the left ventricular wall. Which cellular adaptation is responsible for this finding?
A) Hyperplasia
B) Metaplasia
C) Hypertrophy
D) Dysplasia
Correct Answer: Hypertrophy
Rationale: Hypertrophy is an increase in cell size that occurs in tissues incapable of cell division, such
as cardiac muscle. Chronic hypertension increases afterload, forcing the left ventricle to work harder,
which leads to enlargement of individual myocardial cells. Hyperplasia involves an increase in cell
number and does not occur in cardiac muscle, metaplasia is a change in cell type, and dysplasia
involves disordered growth.
, 5. Which organelle is primarily responsible for oxidative phosphorylation and ATP production within
the cell?
A) Golgi complex
B) Mitochondrion
C) Endoplasmic reticulum
D) Nucleolus
Correct Answer: Mitochondrion
Rationale: Mitochondria are the powerhouse of the cell, responsible for oxidative phosphorylation
and ATP production through the electron transport chain. The Golgi complex processes and packages
proteins, the endoplasmic reticulum synthesizes proteins and lipids, and the nucleolus produces
ribosomal RNA. Understanding organelle function is fundamental to cellular pathophysiology.
6. A patient with a tumor destroying the adrenal medulla would be expected to have a decrease in
which physiological response?
A) Fight-or-flight response
B) Rest-and-digest response
C) Long-term stress response via cortisol
D) Blood glucose regulation via insulin
Correct Answer: Fight-or-flight response
Rationale: The adrenal medulla secretes catecholamines (epinephrine and norepinephrine) that
mediate the sympathetic "fight-or-flight" response. The parasympathetic system controls "rest-and-
digest," cortisol is secreted by the adrenal cortex, and insulin is secreted by the pancreas. Destruction
of the adrenal medulla would impair the sympathetic response.
7. Which genetic disorder follows an autosomal dominant inheritance pattern?
A) Cystic fibrosis
B) Huntington disease
C) Phenylketonuria