patho1 exam
Module 1: Cellular Homeostasis & Regulation ¸
Cellular Transport Mechanisms:
Diffusion: Movement of solutes from high to low concentration
Osmosis: Movement of water across membranes to balance solute concentration
Active Transport: Energy (ATP) used to move substances against concentration gradient
Homeostasis & Feedback Systems:
Hormonal: ADH controls water retention; aldosterone regulates sodium & potassium
Neural: Baroreceptors & osmoreceptors detect blood volume/osmolality → triggers thirst & hormones
Clinical Significance:
Dehydration or fluid overload disrupts cell function
Electrolyte imbalances affect nerves & muscles
Acid-base disturbances impact enzyme function & metabolism
¸ Module 2: Inflammation, Immunity & Cancer Biology
Cellular Stress Responses:
Cells adapt, repair, or undergo apoptosis under stress
Inflammation recruits immune cells to damaged tissue
Innate Immunity:
Immediate, nonspecific defense (macrophages, neutrophils, NK cells)
Inflammatory mediators: histamine, cytokines
Adaptive Immunity:
Specific, slower response involving T & B cells
Memory for faster future response
Cancer Biology:
Genetic mutations cause loss of growth regulation
Oncogenes activate abnormal proliferation
Tumor suppressor genes (e.g., p53) loss → uncontrolled growth
Cancer cells evade apoptosis & immune detection
¸ Module 3: Integumentary & Musculoskeletal Systems ¸
Functions:
Skin: protection, water retention, immune surveillance
Musculoskeletal: support, mobility, hematopoiesis
Common Disorders:
Pressure ulcers: prolonged pressure → ischemia → skin breakdown
Arthritis:
OA: cartilage degeneration, pain with activity
RA: autoimmune inflammation, morning stiffness
Fractures & Healing: inflammation → repair → remodeling
Assessment Tools:
Braden Scale: pressure ulcer risk (lower score = higher risk)
Range of Motion (ROM): joint mobility & stiffness
Quick Reference Charts
Fluid Balance Feedback Systems
Mechanism | Trigger | Response & Effect |
ADH Release | High plasma osmolality | Kidneys reabsorb water → water retention, decreased urine |
Aldosterone Release | Low blood volume or sodium | Kidneys reabsorb Na+, excrete K+ → increases blood volume |
Thirst Reflex | Increased osmolality/low volume | Stimulates drinking → increases fluid intake |
Innate vs Adaptive Immunity
Feature | Innate Immunity | Adaptive Immunity |
Response Time | Immediate (minutes-hours) | Delayed (days) |
Specificity | Nonspecific | Highly specific |
Memory | None | Yes |
Main Cells | Neutrophils, macrophages, NK cells | B cells, T cells |
Function | First line defense | Long-term immunity |
Pressure Ulcer Stages & Braden Scale
Stage | Description | Appearance |
I | Non-blanchable erythema | Reddened intact skin |
II | Partial-thickness skin loss | Blister or shallow open ulcer |
III | Full-thickness skin loss | Ulcer extends into subcutaneous tissue |
IV | Full-thickness tissue loss with exposed bone | Deep ulcer exposing bone or muscle |
Braden Scale:
Scores 6–23, lower score means higher risk
Factors: sensory perception, moisture, activity, mobility, nutrition, friction/shear
Rheumatoid Arthritis vs Osteoarthritis
Feature | Rheumatoid Arthritis (RA) | Osteoarthritis (OA) |
Cause | Autoimmune inflammation | Mechanical wear and tear |
Onset | Gradual, often symmetric | Gradual, asymmetric |
Joint involvement | Small joints (wrists, fingers) | Weight-bearing joints (knees, hips) |
Stiffness duration | Morning stiffness >1 hour | Morning stiffness <30 minutes |
Inflammation signs | Warmth, swelling, redness | Minimal or none |
Systemic symptoms | Fatigue, malaise | Usually absent |