General Anatomy Of Blood Vessels

38 cards
General Anatomy Of Blood Vessels

the Circulatory System Including Blood Vessels, Capillaries, And Veins

Preview Flashcards

Front Back
three principle categories of blood vessels
arteries, veins & capillaries
efferent vessels- carry blood away from heart
afferent vessels- carry blood back to heart
microscopic, thin walled vessels that connect the smallest arteries to teh smallest veins
walls of arteries are composed of 3 layers of
tunica interna
lines inside of the vessel- exposed to blood- consists of simple squamos epith called endothelium
tunica media
mid layer- thickest-smooth muscle, collagen,elastic tiss- strengthen the vess and prevent bp from rupturing them & to provide vasomotion
changes in diameter of a blood vessel
tunica externa
outer most layer- loose connect tiss often merges w. neigh vess anchors the vess and provides pass4small nerves, lymph vess& smaller blood vess
vasa vasorum
small vessels that supply blood to at least the outer half of the wall of a larger vessel
resistance vessles
a.k.a arteries. bc relatively strong resilient tiss struct that resists high bp- constructed to w/stand surges
conducting ( elastic or large) arteries
BIGGEST-expand during ventricular systole to receive blood& recoil during diastole.sub to highest bp& have elastic tiss
Distributing (muscular or medium) arteries
smaller branches that distrib blood to specif organs- interestate highway- 40 layers of smooth musc
resistance ( small) arteries
too variable in # and location to be given individual names- 25 layers of smooth musc & relatively little elastic tiss
smallest of the resistance arteries 40-200Mm w/ only one to 3 layers of smooth muscle
short vessels that link arterioles and capillaries. have individual muscle cells spaced a short distance apart each forming a precap sphinct
precapillary sphincter
encircles entrace to 1 capillary. constrict. shuts off blood flow through their respect cap&diverts blood to tiss or organs elsew
cartoid sinuses
baroreceptors(press sensors) respond to changes in bp- wall of intern carotid artery- monitor bp
carotid bodies
oval recept-3x5mm-sensory fivers of vagus&gloss nerves-monitor blood CO2 O2 and PH
aortic bodies
one to three chemorecptors located in oartic arch near arteries in head & arms- monitor blood comp
blood capillaries
composed of only an endothelium & bment memb-walls .2-.4 mm
where are capillaries scarce?
tendons & ligaments & absent from epithelia, cornea, and lens, and most cartilage
3 types of capillaries
continuous, fenestrated, sinusoids
continuous capillaries
occur in most tissues- enothelial cells-tight juncts-uninterrupted tube- exhibit pericytes
fenestrated capillaries
filtration pores-allow for rapid passage of molecs butretain blood cells & platelets in bstream-kidnesys,endoglands,small I, choroid plex
irregular, highly porous blood spaces in such tissues as liver, spleen& b. marrow-twisted-conform to shape of surround tiss-gaps
lie external to endothelium- contractile proteins- diff into endothelial & smooth mesc cells & thus contrib to vess growth & repair
capillary beds
capillaries organized into these networks- 10 to 100 caps/metarteriole. they continue > thoroughfare channel
thoroughfare channel
leads directly to a venule
capacitance vessles
a.k.a veins- thin walled & flaccid-exp easily to accom an inc vol of blood- greater capactiy for blood contain. than arter. steady flow of blood
smaller veins are calledexih
postcapillary venules
smallest veins-exch fluid with the tissues- very porous
muscular venules
receive blood from postcap venules- up to 1mm in diam- have tunica media of 1 or 2 layers of smooth musc & a thin tunica ext
medium veins
up to 10mm-most veins w. individ names-exhibit infoldings of tunica interna to meet in midd of lumen forming venous valves
varicose veins
failure of venous valves- ppl who stand long time-obesity and preg can promote- press on large veins & obstruct drainage to legs.
varicose veins of anal canal
venous sinuses
veins w. esp thin walls, large lumens, and no smooth musc- ex. coronary sinus of heart- NOT capable of vasomotion
large veins
greater than 10mm- venae cavae, pulmon veins, internal jug, renal veins