CELLULAR ADAPTATION DEFN Flashcards
a bridging discipline involving both basic sciences and clinical practice
Studies the structural and functional changes in cells, tissues and organs that underlie disease states
pathology
the cause
etiology
the mechanism of the development of the disease
pathogenesis
structural alterations in cells and tissues due to the disease process
morphology
functional consequences of the morphologic changes
Clinical signs and symptoms
shrinkage in the size and function of the cells resulting in a decrease in the size of the organ; also decreases function of organ
atrophy
with prolonged disuse, skeletal muscle fibers decrease in number (apoptosis) as well as size
decreased workload
damage to nerves leads to atrophy of muscle fibers supplied by them (traumatic
injury or ischemia of brain/spinal cord)
Loss of innervation (denervation)
ischemia of tissue
Decreased blood supply
muscle wasting (as seen in cachexia - cancer and chronic inflammatory disease, assoc. with chronic overproduction of TNF)
Inadequate nutrition
“self-eating” (cell destroying parts of itself)
- starved cell eats its own components in an attempt
to find nutrients and survive
Increased autophagy
membrane-bound vacuoles containing fragments of cell components
Autophagic vacuoles
cell debris within vacuoles which resists digestion and persist in cytoplasm
ex. lipofuscin granules
residual bodies
“brown atrophy, impart brown discoloration to tissue
lipofuscin granules
increase in size of cell
Hypertrophy
increase in # of cells
Hyperplasia
increases functional capacity of a tissue when needed
Hormonal
increases tissue mass after damage or partial resection
Compensatory
usually caused by excesses or hormones or growth factors acting on target cells (ex. proliferation of uterus after menstruation)
Pathologic hyperplasia
reversible change in which one adult cell type is replaced by another adult cell type, most common epithelial is columnar to squamous typically involving a loss of function; the influences that predispose to metaplasia, if persistent, may initiate
malignant transformation in metaplastic epithelium
Metaplasia