Cellular Adaptation – Pathophysiology Module 2

Vocabulary flashcards covering key terms and definitions related to cellular adaptation, including the major adaptive changes (atrophy, hypertrophy, hyperplasia, dysplasia, metaplasia), their subtypes, and relevant mechanisms from the Module 2 lecture on Pathophysiology.

Homeostasis

The maintenance of a stable internal environment despite external changes.

Cellular Adaptation

Reversible, protective structural or functional changes that cells undergo in response to increased physiological or genetic stress.

Cellular Pathology

Cellular dysfunction arising from excessive physiological or genetic perturbations, often leading to injury or death.

Atrophy

Decrease in cell size or shrinkage, leading to reduced tissue or organ mass.

Hypertrophy

Increase in individual cell size (not due to fluid), resulting in a larger organ or tissue mass.

Hyperplasia

Increase in the number of cells due to elevated mitotic activity.

Dysplasia

Atypical hyperplasia characterized by abnormal size, shape, and organization of mature cells; often considered premalignant.

Metaplasia

Reversible replacement of one differentiated cell type by another, frequently less specialized, cell type.

Physiological Atrophy

Normal, developmentally programmed reduction in cell or organ size (e.g., thymus shrinkage with age).

Pathological Atrophy

Decrease in cell size caused by reduced workload, loss of innervation, diminished blood supply, inadequate nutrition, or lack of hormonal stimulation.

Compensatory Hyperplasia

Adaptive increase in cell number that enables tissue regeneration after loss or damage (e.g., liver regrowth).

Hormonal Hyperplasia

Proliferation of cells stimulated by normal hormonal signals (e.g., estrogen-driven endometrial growth).

Pathologic Hyperplasia

Excessive, abnormal cell proliferation caused by overstimulation from hormones or growth factors (e.g., endometrial hyperplasia leading to abnormal bleeding).

Autophagy

Lysosomal degradation process whereby cells digest their own components to remove debris and recycle nutrients.

Proteasome Up-regulation

Increased activity of cellular protein-degrading complexes that contributes to protein breakdown during atrophy.

Residual Bodies

Cytoplasmic granules containing indigestible material that accumulate in atrophied cells due to incomplete lysosomal degradation.

Cellular Edema

Swelling of cells due to excess fluid; distinct from hypertrophy, which involves increased structural components, not fluid.

Grading of Dysplasia

Classification of atypical cell changes as mild/moderate/severe or low-grade/high-grade, reflecting escalating abnormality and cancer risk.