LN 07 (Disturbance of Growth) Flashcards
sequence of events comprising mitosis
cell cycle
cell cytoplasm and nuclei become enlarge and the nucleoli become prominent, and there occur active production of proteins and ribonucleic acid
G1 phase
marked by active synthesis of deoxyribonucleic acid (DNA) and occupies about 30-40% of the cycle
S phase
phase wherein other preparations for cellular division takes place, and occupies another 10-20% of the cycle
G2 phase
daughter cells are produced which undergo terminal differentiation and are no longer capable of cellular division
M phase (Mitotic phase)
may result in either excess or a deficit of tissue, or may
produce an abnormal pattern of development
disturbances in growth
malformations present at birth
congenital
suggests a complete failure of that tissue or organ to develop
and is therefore absent
agenesis
failure of the tissue or organ to grow and
therefore a rudimentary organ is present
aplasia
used to refer to failure of a tissue to renew itself
aplasia
failure of bone marrow to renew itself that leads to
aplastic anemia
refers to failure of an organ to reach its normal size
hypoplasia
Examples of hypoplasia
- Renal hypoplasia
- Testicular hypoplasia
means absence or closure of a normal body opening
atresia
atresia ani is common in
pigs
adaptive changes of cells and tissues to various
noxious stimuli, particularly those that persist for long periods creating an
increase in the functional demand
acquired abnormalities
implies a reduction in the mass or size of an organ or tissue
atrophy
reduction due to a decrease in the number of cells
numerical atrophy
reduction in the size of individual cells
quantitative atrophy
atrophy that is due to apoptosis
numerical atrophy
occurs in many tissues as part of the normal involution of tissues and organs
physiological atrophy
Mechanic of Physiological atrophy
Do not receive
adequate hormonal stimulation and are no longer wanted
Common examples of atrophy
- involution of the thymus as the animal matures,
- reduction in the
mammary glands of males of species - postpartum changes in the uterus,
- reduction in fetal structures such as the umbilical vessels and ductus arteriosus
also termed as complete atrophy
involution
Pathological atrophy occurs whenever there is deprivation of blood supply, nutritional requirement, or hormonal stimulation as a result of some disease that produces
trophic hormone
due to inadequate dietary intake or in chronic
starvation
nutritional atrophy
as a result of long-standing ischemia
vascular atrophy
due to reduced functional activity such as those
occurring in paralyzed limbs or those held immobile for some time
disuse atrophy
due to long standing pressure that creates inefficient vascular supply to tissues
pressure atrophy
due to loss of trophic hormones such as
that seen in pituitary disease resulting to generalized somatic atrophy
endocrine/hormonal atrophy
Types of pathological atrophy
- Nutritional atrophy
- Vascular atrophy
- Disuse atrophy
- Pressure atrophy
- Endocrine or Hormonal atrophy
- Atrophy due to metabolic, neoplastic, or infectious diseases
a classic response of muscle to denervation
withered or shrunken limb
may be considered complete atrophy
involution of the normal corpus luteum
results in a slow localized loss of cells through degeneration and necrosis, as when an expanding testicular tumor presses on surrounding seminiferous tubules, causing?
pressure atrophy
very important lesion to recognize during
postmortem examination because it is and indication of emaciation
serous atrophy of fat
Some Classical Example of Atrophy
- Withered or shrunken limb
- Involution of the normal corpus luteum
- Pressure atrophy
- Serous atrophy of fat
- Disuse atrophy
Hypertrophy in its pure form occurs only in muscles in response to
increased demand for work
increase in the size of the tissue or organ due to an
increase in the size of individual cells
hypertrophy
an increase in
tissue mass or organ size due to an
increase in the number of
constituent cells
hyperplasia
occurs in those tissues that are incapable of
regeneration, such as cardiac muscles and nerve cell bodies
hypertrophy
following increased hormonal stimulation, as in mammary
gland during lactation
endocrine
especially in paired organ when one is severely
damaged, the other will compensate for the lost function
compensatory
as a response to increased functional demands
functional
as part of the repair process, e.g., healing of fractured
bone, and healing of liver defect by regeneration
replacement
in response to chronic irritation or infection
reactive
Types of hypertrophy and hyperplasia
- Endocrine
- Compensatory
- Functional
- Replacement
- Reactive
- Neoplastic
tumors are formed because of localized areas of increase in cells, and thus, tumors are pathological forms of hyperplasia
neoplastic
when the added tissue mass assumes nodules,
e.g., in liver tissue remodeling
nodular hyperplasia
when they form spaces lined with epithelia, e.g.,
cystic prostatic hyperplasia
cystic hyperplasia
form frond like projections, e.g., hyperplasia of
lining epithelia of tubular organs
papillary hyperplasia
when they form gland-like mass resembling
neoplasm
adenomatous hyperplasia
Hypertrophy and Hyperplasia is best differentiated
histological
adaptive response in which one type of mature differentiated
tissue is replaced by a different but related tissue type
metaplasia
occurs following prolonged irritation
or chronic infection
epithelial metaplasia
reversible and is most commonly seen as a replacement from a specialized tissue type to a less specialized one but more resistant cell type
metaplasia
occurs following prolonged irritation
or chronic infection such as that occurring in urinary stones where the bladder epithelia is changed, and in nutritional deficiencies
epithelial metaplasia
cause squamous metaplasia of esophageal glands and prostate gland
vitamin A deficiency
metaplasia that occurs in association with repair processes
connective tissue metaplasia
Metaplasia does not occur because of alterations in existing mature cells, rather?
depends on the proliferation of germinal cells whose progenies undergo a modified differentiation
proliferative response accompanied by loss of regular differentiation and by cellular atypia and tissue architectural disarray
dysplasia
abnormal growth
dysplasia
Cellular atypia is characterized by (2)
- Pleomorphism (variation in size and shape)
- Hyperchromicity
(increased staining)
most significant finding of serous atrophy of fat
loss of fat from fat depots
Due to inactivity it results to reduction
in size of the organ
disuse atrophy
Microscopically, tissue appear more cellular
due to what appears to be
clustering of nuclei due to
reductions in the amount of cytoplasm
pathological atrophy
Grossly, the tissues or organs are smaller than normal but usually retain their normal shape.
pathological atrophy
Acquired Abnormalities (5)
- atrophy
- hypertrophy
- hyperplasia
- metaplasia
- dysplasia
malformation may occur as a result of
- genetics
- non genetic influence
