Chapter 22: Blood Vessels Flashcards
what are the three layers of blood vessels
tunica interna, tunica media, tunica externa
what type of tissue is tunica interna
simple squamous epithelial
what is the tissue of the tunica interna called
endothelium
what is tunica interna’s function
diffuse molecules
what type of tissue is the tunica media
smooth muscle tissue and elastic fibers
what does tunica media regulate
diameter of the lumen
the tunica media’s constriction of diameter causes
increase in blood pressure and blood flow
what tissue is the tunica externa make of
connective tissue and collagen fibers
what do arteries do
carry blood away from the heart
what is the arteries innervated by
sympathetic autonomic nervous system
what is the function of arteries
stimulates smooth muscle cells to contract and cause constriction of blood vessel walls
what is another name for elastic arteries
conducting arteries
what is the function of elastic arteries
propel blood distally
what are some examples of elastic arteries
aorta, pulmonary trunk, common carotid artery
what is another name for muscular arteries
distributing arteries
where are muscular arteries found
extremities
what is another name for arterioles
resistance arteries
what do arterioles do
regulate blood flow into capallaries
what is the arterioles innervated by
the sympathetic nervous system to regulate resistence
what is the construction of elastic arteries like
largest lumen diameter, thick media, lots of elastic fibers
what is the construction of the muscular arteries like
medium sized, thinner tunica externa, thick tunica internal
what is the construction of the arterioles,
small, no turnica externa, thin tunica internal
what are metarteriole
terminal end of arteriole and entrance into capillaries
what are in metarteriole
precapillary sphincters and thoroughfare channels
what do precapillary sphincters do
regulate flow of blood into capillaries
what do thoroughfare channels do
run through capillary bed to connect to venule
what are anastomosis
joining blood vessels
what are the two type of anastomosis
arterial anastomosis and atriovenous anatomosis
what is the function of arterial anastomosis
alternate route for blood to reach tissue for collateral circulation
what are arterial anastomosis
two or more arteries that supply blod to one capillary bed
what is the function of atriovenous anatomosis
direct flow of blood from arteriole to venule
what is capillaries
network of branched and interconnecting vesselvessels
what is the function of capillaries
exchange of substances and gases like o2 and co2 throughout the tissues
what type of tissues make up capillaries
simple squamous epithelial tissue without a tunica media or externa
what are the three types of capillaries
continuous, fenestrated, and sinusoidal capillaries
what type of tissue is continuous capillaries
complete endothelium
what is function of continuous capillaries
lets water and small solutes diffuse
what are the properties of fenestrate capillaries
endothelium with small pores for rapid exchange of water and solutes
what are some examples of fenestrated capillaries
choroid plexus and endocrine glands
what are the properties of sinusoidal capillaries
endothelium have gaps between cellsto allow water, solutes, and proteisn through
what are some examples of sinusoidal capillaries
liver and bone marrow
what do veins do
carry blood back to the heart
what are venules
groups of capillaries that unite, are thin and have no tunica media
what are veins
merged venules with a thick tunica externa and thin media
what are some examples of veins
varicose veins, hemorrhoids
what is the portal system
blood flow from one capillary network to another before flowing through the heart
what are examples of ptal systems
hypothalamus to anterior pituitary and hepatic portal system
describe blood flow
heart to elastic arteries to muscular arteries to arteries to metarterioles to capillaries to venules to veins to heart
