Chapter 4 Altered Cellular and Tissue Biology Flashcards
Cellular Adapation
Reversible response to physiologic and pathologic changes
5 types of adaptive changes
- Atrophy
- Hypertrophy
- Hyperplasia
- Dysplasia
- Metaplasia
Atrophy (2)
- Decrease in cell size
- Decrease in organ size if enough cells shrink
Atrophy Normal vs. Pathologic
- Normal: early development
- Pathologic: Results from decreases in workload, pressure, use, blood supply, nutrition, and hormonal/neural stimulation
Hypertrophy (2)
- Increase in cell size
- Increase in organ size
Hypertrophic physiologic occurance
Results from increased demand, stimulation, hormonal stimulation, growth factors
Hypertrophic pathologic occurance
Results from chronic hemodynamic overload
Hyperplasia (2)
- Increased number of cells
- Increased rate of cellular division
Hyperplasia physiologic occurrence (2)
- Compensatory: enables organs to regenerate
- Hormonal: in organs that respond to endocrine hormonal control
Hyperplasia pathologic occurrence
Abnormal proliferation of normal cells
Dysplasia (3)
- Abnormal changes in size, shape, organization, of mature cells
- May be reversible if triggering stimulus is removed
- Tissue appears disorderly, but is not cancerous
Metaplasia (3)
- Reversible replacement of one mature cell type by another
- Associated with tissue damage, repair, regeneration
- Reprogramming of stem cells or undifferentiated mesenchymal cells
Reversible cellular injury
Cells can recover
Irreversible cellular injury
Cells die
Hypoxic injury (7)
- Most common
- Ischemia
- Reduced oxygen
- Decreased hemoglobin
- Decreased RBC production
- Decreased RR
- Oxidative enzyme poisoning
