homeostatsis Flashcards
Homeostasis
set point
lack of homeostasis
forms basis of most diseases
adaptation
allows cells to survie short-term
cellular adaption
allows cells to survive short term
Physiological/pathological consequences if homeostasis isn’t returned.
r eversible cell injury-irreversible-cell death Most physiological process are goverened by negative feedback mechnisms exceptions are hemostatsis and parturition.
Morphologic charcteristics
Excessive cell swelling and dramatic changes to organelles. Hydrophic
Hallmark of irreversible cell injury or death
Massive Ca+ influx
Cell death
Necrosis
Apoptosis
Homeostasis
dynamic processe to response to stress or injury
Regulated Variables
have a physical receptor eg. temperature and BP
Afferent Pathway
information relayed via afferent to integrating center
Set point
range of normal values
Efferent pathway
carries departures from normal to alter controlled variables as part of effector response
Negative feedback
work to return the orginal input signal back to wnl.
Physical receptors
thermoreceptors, baroreceptors, chemoreceptors, osmo and mechanoreptors
controlled variables
vasoconstriction, vasodilation, increase heart rate, sweat reponse, muscle contraction
Pathology
can be caused by intrinsic (genetic) or extrinsic environmental stress or injury.
Genetic causes
mayh be inherited mutations from parent
acquired
mutations from the environment
diseases can be both
genetic and environmental
diseases offer specific process
inflammation or autoimmunity
etiology
underlying cause of disease
Understanding disease process allow you
to inform, dx, rx, and prevent disease
Down syndrome is not
inherited, acquired congenital during process
Normal cell goes from
adapted, reversible cell injury, irreversible cell injury-cell death
Atrophy
shrinkage of tissue or reduction in cell size
Hypertrophy
increase in cell size in response to stress
Hyperplasisa
increase in cell number
Metaplasia
reversible process where one mature cell is replaced by another less mature cell type
Type of cells that are replaced in smoking
Different type of lining, barrets esophagus
Dysplesia
Disordered growth and maturation of cellular components of tissue
Cellular accumulations and calcifications occur in response to injury and subsequent manifestations of cellular damage
Under stress cells…
Accumulate substances,
Acumulationg substances may lead to …
cell injury or cell death and provide INDICATIONS of cell injury
Lipids are found in
heart and liver
Glycogen
particular in liver and skeletal muscle
Melanin
Melanocytes in the skin
Hemosiderin
formed from hemoglobin-iron
Bilirubin found
liver
Hyaline change is
non-specfic indicator -formed from protein, seen cartilage, may intefere with metabolic or physical fx, thus tissue.
Inflammatory response
can lead to further injury
