Module 4 Flashcards
Cellular adaptation
when a cell changes it structure or function to better promote homeostasis
This further changes the DNA in the cell
There are many factors that cause cellular damage and/or destruction such as
changes in metabolism, decreased adenosine triphosphate (ATP), and…
Cellular stressors - Tissue ischemia
Triggered by obstructed artery or respiratory disorder
Causes decrease blood supply to tissues
Leads to decreased oxygenation
Results in decreased cellular metabolism (aerobic)
Brain, heart, and Kidney most affected due to high oxygen use, causing hypoxia, or lacking oxygen
Sever oxygen deficit inhibits energy production (ATP)
Failure of sodium pump and other cellular functions
Increased sodium inside the cell causes cell to enlarge and rupture
Other changes include lactic acid buildup due to anaerobic metabolism
Cellular stressors - Extreme temperatures
Physical damage related to heat or cold temperatures
Cellular stressors - radiation exposure
Alter cellular contents
Changes DNA
Cellular stressors -Physical tissue damage
trauma or injury damages cells
Cellular stressors - chemical toxins
Endogenous and exogenous chemicals can;
-Change the permeability of the cell membrane
-Produce other chemicals such as free radicals
Cellular stressors - microorganisms
Bacteria, viruses, and other pathogens can injure cells
Cellular stressors - Abnormal Accumulation of Metabolites in cells
Genetic defects or inborn errors of metabolism can cause byproducts to accumulate in cells and lead to cellular damage
cellular stressors - Nutritional Deficits
Vitamin deficiencies can prevent normal metabolism from occurring
minor/repairable cell damage
Initial damage changes metabolic reactions that lead to a change/loss of cellular function
Anaerobic metabolism happens within the cell, leading to lactic acidosis (build up of lactate production from oxygen deprivation)
The damage in minimal, the cell recovers, and normal function returns
Major/not repairable cell damage
Noticeable morphologic and structural damage to the nucleus and cell wall occurs - this leads to cell death
Post cell death
Nucleus disintegrates
Cell lyse releasing lysosomal enzymes into body tissues
Triggers inflammation process
-Swelling, redness, pain
-Damages nearby cells
-Enzymes release into vascular system
Diagnostic laboratory testing to detect specific enzymes that are released from dead cells
-Cardiac enzymes being released from myocardial cells when they are damaged during a myocardial infarction
Cell death
This leads to cell death
Swelling in the cell
Lipid accumulation in the cell
Cell membrane ruptures
Atrophy
-Decrease in cell size
causes;
-Decrease in tissue mass
Loss of function
Poor nutrition
-Decreased neurologic or hormonal stimulations
Aging
ex;
Skeletal muscle shrinkage from an extremity being immobilized in a cast for several weeks
Hypertrophy
Increase in cell size
larger tissue mass
causes;
Increased workload on tissue
Pregnancy
ex:
Heart muscle enlargement due to increased blood pressure and blood volume
Prostate tissue enlarging due to decreased testosterone levels in aging adult men
Hyperplasia
Increased number of cells
Enlarged tissue mass
Sometimes hypertrophy and hyperplasia occurring simultaneously
causes;
Pregnancy
Compensatory mechanisms to meet increased demands
Pathologic when hormonal imbalance
ex:
Can increase cancer risk
Callus formation on the bads of a construction worker
Gums displaying hyperplasia due to phenytoin (Dilantin), an anticonvulsant drug
Metaplasia
One mature cell type being replaced with another mature cell type
causes;
Vitamin A deficiency
Adaptive mechanism to provide more resistance against carcinogens and irritants
Ends up decreasing resistance
ex:
Stratified squamous epithelium cells replacing ciliated columnar epithelium cells in the respiratory tracts of cigarette smokers
Resistance decreasing due to disappearance of cilia normally found in ciliated columnar epithelial cells in the lungs; and the cilia removing debris
Dysplasia
Cells varying in size and shape
Contain large nuclei
Increased mitotic rate
causes;
Results from chronic irritation, infection, or a precancerous change
ex:
Dysplastic cells detected in pap smear (Papanicolaou test) done for the detection of cervical cancer cells
Anaplasia
Undifferentiated cells
Look nothing like original parent cell due to mutation
Variable nuclear and cell structure
Multiple mitotic figures
causes;
Also results from chronic irritation, infection, or is a precancerous change
ex:
Characteristic of cancer
Basis of grading the aggressiveness of malignancy
Neoplasia
Means new growth
Commonly referred to as a tumor
Benign
-Non-cancerous
-Do not spread
-Usually not life-threatening
Malignant
-Cancerous
causes:
Malignant neoplasms caused by irritants or carcinogens
ex:
A cancerous growth in the lungs (malignant neoplasm)
A non-cancerous growth on the skin (benign neoplasm)
