NURS 6501 – Week 1: Cellular Biology &
Adaptation
Walden University | Advanced Pathophysiology | Study Guide
Core Concepts
1. Cellular Function
Component Function
Nucleus Control center; stores DNA
Mitochondria Energy production (ATP)
Ribosomes Protein synthesis
Endoplasmic Reticulum Protein (rough ER) & lipid (smooth ER) processing
Golgi Apparatus Modifies, packages proteins
2. Cellular Adaptation
Type Example Reversible?
Atrophy Muscle shrinkage from immobility Yes
Hypertrophy LV hypertrophy in HTN Yes
Hyperplasia Endometrial thickening Yes
Metaplasia Smoking → columnar to squamous Yes
Dysplasia Cervical dysplasia (HPV) Potentially
Key Pathophysiology Terms
• Apoptosis: Programmed cell death (normal)
• Necrosis: Uncontrolled cell death → inflammation
• Free Radicals: Cause oxidative stress → DNA damage
• Hypoxia: ↓O2 → ATP depletion → cell swelling → lysis
, Clinical Example:
Patient Case: A 52-year-old male with chronic hypertension presents with left ventricular
hypertrophy seen on echocardiogram.
Mechanism: Increased workload → myocyte hypertrophy → increased muscle mass (compensatory
response).
NCLEX Tip: Hypertrophy can be physiological (exercise) or pathological (HTN).
NCLEX-Style Questions (with Rationales)
1. Which of the following best describes metaplasia?
A. Programmed cell death
B. An increase in cell number
C. A reversible change in cell type
D. Permanent damage due to toxins
Answer: C – Metaplasia is a reversible change where one adult cell type is replaced by another,
usually due to chronic irritation (e.g., smoking).
2. What is the most common cause of cellular injury?
A. Infection
B. Trauma
C. Hypoxia
D. Radiation
Answer: C – Hypoxia is the most common cause, leading to ATP depletion and eventual cell
death.
Summary Sheet (For Quick Recall)
• Reversible changes = atrophy, hypertrophy, hyperplasia, metaplasia
• Irreversible = dysplasia → potential for malignancy
• Hypoxia = #1 cell injury → ↓ATP → swelling
• Apoptosis ≠ inflammation, necrosis = inflammation
NCLEX-Style Practice Questions (10 Total) — With Rationales
1. Which of the following best describes metaplasia?
A. Programmed cell death
B. An increase in cell number
C. A reversible change in cell type
D. Permanent damage due to toxins
Adaptation
Walden University | Advanced Pathophysiology | Study Guide
Core Concepts
1. Cellular Function
Component Function
Nucleus Control center; stores DNA
Mitochondria Energy production (ATP)
Ribosomes Protein synthesis
Endoplasmic Reticulum Protein (rough ER) & lipid (smooth ER) processing
Golgi Apparatus Modifies, packages proteins
2. Cellular Adaptation
Type Example Reversible?
Atrophy Muscle shrinkage from immobility Yes
Hypertrophy LV hypertrophy in HTN Yes
Hyperplasia Endometrial thickening Yes
Metaplasia Smoking → columnar to squamous Yes
Dysplasia Cervical dysplasia (HPV) Potentially
Key Pathophysiology Terms
• Apoptosis: Programmed cell death (normal)
• Necrosis: Uncontrolled cell death → inflammation
• Free Radicals: Cause oxidative stress → DNA damage
• Hypoxia: ↓O2 → ATP depletion → cell swelling → lysis
, Clinical Example:
Patient Case: A 52-year-old male with chronic hypertension presents with left ventricular
hypertrophy seen on echocardiogram.
Mechanism: Increased workload → myocyte hypertrophy → increased muscle mass (compensatory
response).
NCLEX Tip: Hypertrophy can be physiological (exercise) or pathological (HTN).
NCLEX-Style Questions (with Rationales)
1. Which of the following best describes metaplasia?
A. Programmed cell death
B. An increase in cell number
C. A reversible change in cell type
D. Permanent damage due to toxins
Answer: C – Metaplasia is a reversible change where one adult cell type is replaced by another,
usually due to chronic irritation (e.g., smoking).
2. What is the most common cause of cellular injury?
A. Infection
B. Trauma
C. Hypoxia
D. Radiation
Answer: C – Hypoxia is the most common cause, leading to ATP depletion and eventual cell
death.
Summary Sheet (For Quick Recall)
• Reversible changes = atrophy, hypertrophy, hyperplasia, metaplasia
• Irreversible = dysplasia → potential for malignancy
• Hypoxia = #1 cell injury → ↓ATP → swelling
• Apoptosis ≠ inflammation, necrosis = inflammation
NCLEX-Style Practice Questions (10 Total) — With Rationales
1. Which of the following best describes metaplasia?
A. Programmed cell death
B. An increase in cell number
C. A reversible change in cell type
D. Permanent damage due to toxins
