circulation Flashcards
one heart beat
sends blood through both systemic and pulmonary circuits
layers of vessels
-intima, media and adventita
intima
endothelium and connective tissue
media
smooth muscle
adventitia
support the shape and have collagen/ elastic fibers
vasoconstriction
sympathetic nervous system
-r and d
-constricts sooth muscle/ media
walls of the vessels are too thick?
vasa vasorum (blood supply soly to supply the vessels w nutrients)
Arteries vs veins
-arteries have thicker walls, maintain circular shape, folds in the inima and end at continuous capillaries
-venules will collapse if cut and end at fenestrade capillaries
fenestrated capillaries
have pores, endotherlium and basal lamina
continuous capillaries
endothelium and basal lamina
diameter of capillaries
8 microns
capillary diffusion types
-diffusion
-pores
-endocytosis
-gaps in the cell linnings
where do capillaries lead
capillary beds
capillary beds
capillary network of vessels that connect arterioles and venules
collateral arteries
-brain heart and tummy
-places that have multiple artery supply and if one gets a clot its fine
capillaries are what kind of cell?
simple squamous epithelium
what anastomosis do collateral arties form?
arteriole anastomosis
Second type of anastomosis?
-arterioventricular anastomosis at places where movement hinders blood flor and there is a direct connection between arterioles and venules (joints and organ)
artery decreasing in size
elastic artery-> muscular artery-> arteriole
layers of venules
endothelium and adventitia
arterioles
-media, endotherlium and basal lamina
elastic artery
has elastic in the intima
venous valves
help blood flow against gravity and if they dont close you get varicose veins
vein blood volume
60-70%
-distend 8x more than arteries
artery blood volume
30-35%
