Cellular adaptations L4 Flashcards
why do cells undergo hypertrophy ?
due to synthesis of more cell organelles and cytoplasmic structural proteins.
what type of cells undergo hypertrophy?
cells that are unable to divide
what would be an example of physiologic hypertrophy and what would be an example of pathologic hyper trophy?
physiologic hypertrophy would be skeletal muscle hypertrophy in athletes and hypertrophy of smooth muscles of pregnant uterus while pathologic hypertrophy would be left ventricular hypertrophy in long standing hypertention
what type of cells undergo hyperplasia?
cells that are capable of dividing .
what cell adaptations cause increase in organ size?
hyperplasia and hypertrophy
why do cells undergo Atrophy?
due to loss of cell substance and cell-cell loss.
what is cell-cell loss
one cell holds another cell with certain intermediate filaments which are present between cells .when this cell-cell connection is lost there will be shrinkage in cell size.
what are the types of atrophy?
decreased workload (disuse atrophy)
pressure atrophy
inadequate nutrition
loss of nerve supply
what is dysplasia usually paired with?
dysplasia usually occurs after metaplasia
what is the difference between genotype and phenotype ?
phenotype is the difference in the appearance , development and behavior , genotype is the genetic pattern
why does Atrophy occur?
because there was a loss in cellular contents such as proteins
increased growth factor or growth hormones in the body means more is demanded , what cell adaptation occurs in order to try and fulfill this demand ?
hyperplasia or hypertrophy
describe the arraignment of cells after metaplasia
uncoordinated and misaligned
what cellular adaptation may result from chronic irritation ?
metaplasia
give examples of physiological and pathological hypertrophy .
muscle growth due to exercise and hypertrophy of smooth muscles of the pregnant uterus are physiological
an example of pathologic hypertrophy is the left ventricular chamber of the heart being enlarged due to hypertension
give some examples of physiological and pathological hyperplasia
physiological :
increase in number of smooth muscles in the uterus due to normal increase in estrogen levels during pregnancy
increase in number of glands due to normal increase in estrogens and prolactin in lactating breast
pathological :
increase in number of connective tissue fibroblasts and blood vessels in wound healing in response to excessive growth factors released at site of injury .
give some examples of physiological and pathological atrophy
physiological atrophy would be the thymus gland undergoing atrophy in childhood or the uterus decreasing in size shortly after child birth
pathological atrophy would be
decreased workload
pressure (compression of tissue surrounding a growing tumor )
inadequate nutrition
loss of nerve supply( interruption of nerve supply leads to wasting of muscles and paralysis ) viral infection like polio
aging
- shrinkage of brain
- osteoperosis (in women mostly )
loss of endocrine stimulation
loss of blood supply ( adaptation before necrosis
where are columnar cells present ?
respiratory epithelium
give an example of pathological metaplasia /
smoking transforming columnar epithelium in respiratory system to squamous cells
what other cellular adaptations often accompany dysplasia ?
metaplasia and hyperplasia
