microscopic structure and function Flashcards
state 3 layers of the heart
inner layer- endocardium
middle layer- myocardium
outer layer- epicardium
how are cardiac muscle cell connected
intercarlated discs
what does intercarlated discs provide
anchorage
electrical communication
what can be found in myocardium?
contractile cardiac muscle (t tubule system, lipid droplets, mitochondria, glycogen granules)
fibroblast
blood vessels
nerves
pacemaker cells
secretory cells
cardiac conduction system cells
intercarlated disc consist of
gap junctions
desmosome
where gap junctions located
longitudinally oriented regions
what does gap junction do
provide ionic continuity between adjacent cells
where can desmosomes be found
at transverse regions of discs
what does desmosome do
bind adjacent cells togethee
gap junction consist of
connexin
connexon
chanel
desmosome consist of
cadherins
anchoring protein like desmoplakin and plakoglobin
fascia consist of
cadherins
anchoring protein like catenins, vincilin and alpha actinin
how calcium enter the sarcoplasm
thru L-type calcium chanels
how calcium released into the cytosol
via ryanodine receptors
