A&PII ch. 20

excepting to arteries and veins direction

pulmonary

65% of blood is in

veins

tunic interna

lines the blood vessels, consists of endothelium, cell adhesion causes leukocytes to congregate in tissues where their defensive actions are needed

tunica media

middle layer, consist of smooth, collagen, and elastic tissue, strengthens vessels,…

tunica external

outernost layer

why is smooth muscles not in capillaries

conducting (elastic or large arteries)

biggest, internal elastic lamina at the hard

distributing (muscular or medium) arteries

distribute food to specific organs, soothe muscle layers constitute ¾ all thickness, internal and external elastic laminae are thick

resistance (small) arteries

thicker media in proportion to their lumen than large arteries… notes

metarterioles

short vessels that link arterioles direction to ventrules in some places, provide shortcuts allowing blood bypass capillary beds

aneurysm

weak point in artery or heart wall

dissecting aneurysm

blood accumulates between tunics of artery and separates them usually because of degeneration of the tunica media

arterial sense organs

sinusoids

found ink liver, bine marrow, spleen, irregularr blood filled spaces…

capillary beds