Cellular Adaptation Flashcards
(45 cards)
Examples of cellular adaptation
Thymus decrease Atrophy Weight lifting Hypertrophy Inadequate nutrition Atrophy Horizontal stimulation of prostate gland Hyperplasia
Describe cellular injury
A sequence of events which occur when the adaptive ability of a cell is exceeded.
Injury May be reversible up to a certain point
If the stimulus persist, irreversible injury may result
What causes cellular injury
Oxygen deprivation Physical agents Chemicals/drugs Infectious agents Immunologic reactions Genetic derangements Nutritional imbalances
Example of dysplasia
Cervical dysplasia
Changes in epithelial cells of cervix (hpv)
Examples of metaplasia
Smoker -Pseudostratified tissue Replaced with one mature tissue type stratified squamous
Metaplasia
Reversible replacement of one mature type for another sometimes less differentiated cell type
What are abnormal stimulus hypertrophy and Hyperplasia ?
Increased functional demand (myocardium)
increased work demand (muscles)
metabolic demand
excess endocrine stimulation
Examples of Hypertrophy
Hypertrophy increase in size of cells and consequently the organ.
Weight lifting
Uterus with pregnancy
Heart muscle (abnormal) - hypertrophic cardiomyopathy
Atrophy
decrease or shrinkage in cell size, resulting
in a reduced tissue mass
Hypoxia
Reduced oxygen in tissue
Ischemia
decreased supply of oxygenated blood to tissue or organ due to circulatory
obstruction
Examples of Hyperplasia
Hyperplasia increases number of cells resulting from increased rate of cellular division. Enlarged tissue mass.
Enlarged prostate
endometrial hyperplasia
Necrosis
Premature death of cells and living tissue
apoptosis
programmed cell death
ATP Depletion
a major component of the injury is the alternation of membrane permeability cause by decreased activity of ATP
- dependent iconic pumps
Main cellular mechanism of cell Injury
ATP Depletion
Loss of Calcium homeostasis
oxidative stress
damage to mitochondria increased permeability of membranes
Principles regarding cellular response to injury and consequences
response depends on nature of injury, duration & severity
consequences of injury depend on cell type
although different agents may have different initial cellular targets. The final pathways are often similar
Why does oxygen deprivation occur?
impaired energy production
intercellular accumulation of water and electrolytes
changes in structure & size of organelles
cells switch from aerobic and anaerobic metabolism
Hypoxic conditions
trauma, stroke, respiratory diseases, unstable angina, organ failure, cancer, hemorrhagic stroke, peripheral arterial disease, congestive heart failure & heart attack
Cellular Metabolism
sustains life and allows cells to grow develop, repair damage and respond to
environmental changes
Describe the concepts of cellular adaptation
changes in conditions or stressors
cell usus reserves to continue functioning
cell produces adaptive changes to continue functioning
If reserves insufficient cell injury or death occurs
Dham- Atrophy, hypertrophy, hyperplasia, dysplasia and metaplasia
Dysplasia
a pre-neoplastic condition resulting in a alteration on in size, shape & organization of
cellular components of tissue.
What are 5 causes of Atrophy?
Reduced use of the tissue Inadequate nutrition loss of endocrine /hormonal stimulation loss of nerve supply aging
Describe the etiology (cause of disease) and pathogenesis (development of disease) process involving alteration in cellular function and growth
Disease may develop when cells and structure, function change, homeostasis cannot be maintained as a result.
Change in cell DNA
Cell damage or destroyed by changes in metabolic processes, reduced ATP, Altered PH of cells
Damage to cell membrane and receptors
