adaptations Flashcards
(97 cards)
are reversible changes in the
number, size, phenotype, metabolic activity or functions of cells in response to changes in their
environment.
Adaptations
Physiologic adaptations
Pathologic adaptations
An adaptation to stress can progress to functionally significant__
if the stress is not relieved
cell injury
◦ Represent responses of cells to normal stimulation by _ or _
_–induced enlargement of the breast
and uterus during pregnancy
Demand of _
physiologic Adaptations
- hormones or endogenous chemical mediators.
- Hormone
- mechanical stress
◦ Responses to stress that allow cells to modulate their structure and function.
eg_
pathologic Adaptations
- Squamous metaplasia of bronchial epithelium in smoker
- is an increase in the size of cells
resulting in increase in the size of the organ.
◦ No new cells, just bigger cells, enlarged by an
increased amount of _ and _
◦ Occurs in tissues incapable of cell division
Hypertrophy
- structural proteins and organelles
Hypertrophy
◦ Physiologic Cellular
Hypertrophy
- Pathologic Cellular
Hypertrophy
Enlargement of the uterus
during pregnancy
Increased work load the
striated muscle cells in
both skeletal and heart
Physiologic Cellular
Hypertrophy
– removed for postpartum
bleeding.
- large, plump hypertrophied
smooth muscle cells from a
__
- a gravid uterus
- B, Small spindle-shaped
uterine smooth muscle cells
from a __
normal uterus.
Cardiac enlargement that
occurs with hypertension
or aortic valve disease
Pathologic Cellular
Hypertrophy
The type of reversible injury is __, and the irreversible
injury is _
ischemia
ischemic coagulative necrosis
In__ , the left ventricular wall is
thicker than 2 cm (normal, _)
myocardial hypertrophy
- 1–1.5 cm
an enzyme substrate that
colors viable myocardium _. Failure to stain is due
to enzyme loss after cell death
triphenyltetrazolium chloride
- magenta
Two types of physiologic hyperplasia:
hormonal hyperplasia
compensatory hyperplasia
exemplified by the proliferation of the glandular epithelium of the female breast at puberty and during pregnancy
hormonal hyperplasia,
in which residual tissue grows after removal or lossof part of an organ
compensatory hyperplasia
- Occurs due to an abnormal stressor
Pathologic Hyperplasia
Excessive hormonal or growth factor stimulation
Endometrial hyperplasia
Benign prostatic hyperplasia
Papillomavirus
shrinkage in the size of the cell by the loss of cell
substance
◦ Decreased cell and organ size as a result of decreased
nutrient supply or disuse
◦ Associated with decreased synthesis and increased proteolytic
breakdown of cellular organelle
atrophy
causes of atrophy
Decreased Workload
Loss of Innervation,
Diminished Blood Supply,
Inadequate Nutrition,
Loss of Endocrine Stimulation,
Aging (Senile Atrophy)
combination of decreased Protein synthesis because of reduced metabolic and increased protein degradation in cells occurs
mainly by the _
◦ increased __
MECH OF ATROPHYY
ubiquitin-proteasome pathway.
autophagy
types of atrophy
PHYSIOLOGIC ATROPHY
SENILE ATROPHY
PATHOLOGIC ATROPHY
-occurs as a natural consequence of maturation
◦ __ and __ during
puberty.
◦ Sexual organs and brain begin to undergo at about _ of age
PHYSIOLOGIC ATROPHY
- atrophy of the thymus and lymphoid tissues
- 50 years
-occurs in old age characterized by dry, lusterless,
wrinkled skin due to atrophy of sweat and
sebaceous glands and loss of fat, gray hair, atrophy
of the ligaments, brittle bones which easily break
SENILE ATROPHY