what is homeostasis
steady state maintained in response to physiological demands
4 possible responses to stress
3 purposes of adaptive cell repsonses
4 types of adaptations
def. hyperplasia
increase in # of cells, resulting in increased mass of tissue or organ
2 features of hyperplasia
2. reversible
mech. of hyperplasia
stim of cell cycle by growth factors, more mature cells
4 pathologic hyperplasia
2 phsyiological hyperplasia
2. compensatory
def. hypertrophy
increase in cell size leading to larger organ
3 feat. of hypertrophy
mech of hypertrophy
increased synthesis of structural proteins and cellular components
2 physiological hypertrophy
2. hormonal
2 pathological hypertrophy
2. bladder muscle
def. atrophy
decrease in size and/or number of cells
is atrophy reversible?
yes
2 normal atrophy
2. reversal of hyper
mech of atrophy
increased protein degradation and decreased synthesis
5 examples of pathological atrophy
def. metaplasia
change of one MATURE cell type to another
4 feat. of metaplasia
normal metaplasia
ONLY one - squamous metaplasia in cervix
mech of metaplasia
reporogrammming of epithelial stem cells
4 patho metaplasias