microscopic anatomy of the heart and blood vessels anatomy Flashcards
cardiac muscles are striated with troponin T or F
T (troponin bc of the alternating thick and thin filaments)
myofibrils are
bundle of protein filaments that contain the contractile elements of the cardiomyocyte
Sarcomere
smallest contractile unit in the myofibril
intercalated discs and gap junctions allow rapid flow of repolarization or depolarization signal?
depolarization signal
cardiac muscles have rhythm and contract spontaneously T or F
T
Light bands/I bands
thin filament - contain ACTIN
Dark bands/A bands
thick filaments (run entire length) contain myosin
tunica externa/adventitia contains what
collagen and elastic fibers
tunica externa/adventitia roles
protects the vessel, prevent over expansion, anchors to surrounding tissue
tunica media is a smooth muscle that contains
large arteries that have an external elastic lamina
tunica intima 3 layers
- endothelium - simple squamous epithelium
- subendothelium - loose connective tissue, maiy larger vessels
- basement membrane/internal elastic lamina
capillaries also contain 3 vessel wall layers T or F
F, only tunica intima layer
capillaries function
Connect arterial & venous systems, exchange nutrient, oxygen & waste
3 types of capillaries
continuous, fenestrated, and sinusoidal
continuous cap.
no pores or fenestrae ex. in muscle, connective tissue, & nervous tissue