Blood vessels Flashcards
(36 cards)
Tunica Intima Layers
Endothelium
Sub-endothelial layer
Internal elastic lamina (arteries only)
Tunica media layer
external elastic lamina
Tunica externa
vasa vasorum
Largest arteries
Elastic arteries (conducting)
Elastic arteries have
prominent Internal and elastic lamina
Characteristics of muscular arteries
thick tunica media.Prominent internal elastic lamina.
Arterioles consist of
endothelium and 3-5 layers of SM
Metaarterioles
SM not continuous but spaced. Allows them to function as a sphincter.
Contraction of AV shunt sends blood to
capillary bed
Relaxation sends blood through thoroughfare channels
to venues by passing cap bed
Continuous capillary
continuous endothelium , continuous basal lamina
Fenestrated
continuous BL , porous endothelium
Sinusoidal capillaries
porous endothelium , and discontinuous BL
T intimate of veins
endothelium , some contain valves
T media of veins
mostly CT fibers , some SM
T adventitia of veins
most prominent tunic in medium and large veins . SM is oriented longitudinally
Lymph vessels lack what?
BM
3 phases of blood clotting
Adhesion of platelets
Aggregation of platelets
platelet pro coagulation activity terminates with the removal of the fibrin clot
Extrinsic path
Factor 7 and X
Intrinsic path
Factors 7, 8, 9, 11, X
Common pathway
activated factor X cleaves prothrombin to thrombin
thrombin cleaves fibrinogen to fibrin
Factor 13 then cross links the fibrin monomers making stable fibrin polymer which entraps platelets to prevent blood loss.
Systemic circuit
LV Aorta Elastic artery Muscular artery Arteriole Capillary Small venule Large vein Vena cava RA RV
Veins have more muscle that runs
longitudinal
PKC does what regarding blood clotting
Turns off the clotting , so high PKC leads to hypercoaguability
