Organ Histo Final Flashcards
Elastic arteries aka? Give 5 examples of these elastic arteries. Where are they typically found?
aka conducting arteries; common iliacs, carotid, aorta, brachiocephalic, subclavian arteries (ccabs); largest arteries typically found closest to heart)
In which type of arteries, elastic or muscular, is there a common & well-developed internal elastic lamina of the tunica intima? Which tunica media is mostly composed of many fenestrated elastic laminae? Which tunica intima has a thin/incomplete internal elastic lamina? Which tunica media is mostly smooth muscle and richly innervated w/sympathetics for pinpoint control of lumen size for blood flow?
muscular; elastic; elastic; muscular
Comment on the tunica intima of elastic arteries (conducting).
-attenuated epithelium w/rounded nuclei, thin or incomplete internal elastic lamina, thicker CT including collagen I, elastic fibers, smooth muscle cells & fibroblasts
Which layer of both elastic & muscular arteries is typically most dominant? Which layer contains the endothelium & is closest to the lumen? Which layer typically contains the vasa vasorum, small blood vessels that supply nutrients & O2 to the larger blood vessels?
tunica media; tunica intima; tunica adventitia
In the elastic arteries, what is the tunica media mainly comprised of? What is its’ function? What else is found in the tunica media of these conducting arteries?
many fenestrated elastic laminae; function-for expansion & recoil; there also is found a thin external elastic lamina, and vasa vesorum are common in the outer portions of the tunica media of elastic arteries
Which layer of the elastic arteries is composed of loose fibroelastic CT w/numerous vasa vasorum?
tunica adventitia
Muscular arteries aka? What are 4 examples of these?
aka distributing arteries; brachial, radial, renal, femoral arteries (BRRF)
Which layer of the muscular arteries has a common, well-developed internal elastic lamina w/endothelium & a few smooth muscle cells possible?
tunica intima
The tunica media of muscular arteries (distributing) is primarily composed of? It is richly innervated w/? Is an external elastic lamina possible? name some other structures found in the tunica media.
primarily circular smooth muscle; richly innervated w/sympathetics to control blood flow; an external elastic lamina is possible (more often found in elastic arteries); also found gap junctions btwn. smooth muscle cells & elastic fibers, reticular fibers, & chondroitin sulfate
What is found in the tunica adventitia of muscular arteries?
fibroelastic CT w/sulfated GAG’s, fibroblasts, & vasa vasorum
Name the 3 different types of arteries we discussed.
- elastic arteries (conducting)
- muscular arteries (disbruting)
- arterioles (small muscular arteries)
In arterioles, lumen size is relatively equivalent to what?
the wall width
Arterioles are considered a smaller version of?
muscular arteries
T/F: In arterioles, there is a well-developed external elastic lamina.
False; no external elastic lamina
Name 2 of the blood vessels that have an internal elastic lamina possible, but not well-developed in most cases.
elastic arteries, arterioles
These arteries see an increase in width into their 20’s where the wall gets thicker, especially the tunica media (increased # of elastic laminae).
elastic arteries (conducting)
These arteries see collagen I & various proteoglycans increasing in their wall, decreasing their flexibility (which is particularly a problem in which vessels)? What age bracket do they do this?
muscular arteries (distributing); particularly a problem in coronary vessels; typically occurs into middle age
With hypertension, typically around the 50’s in age, elastic fibers break down & are not sufficiently replaced; collagen I & proteoglycans end up accumulating in the tunica _, resulting in an increase in _ BP?
media; systolic
Arteriosclerosis aka? Primarily occurs in which arteries? which layer becomes infiltrated w/soft lipids, causing lumen diameter to decrease? Which layer can have collagen I & sulfated GAG’s build up?
aka atherosclerosis or “hardening of the arteries”; primarily occurs in elastic arteries; tunica intima causes decreased lumen diameter; tunica media can have collagen I & sulfated GAG’s accumulate
What is the main problem w/elastic arteries and atherosclerosis that causes the tunica intima to have trouble surviving?
blood is moving very fast
With blood moving so fast in atherosclerosis, which layer is prone to injury, irritation & infection? If there is an accumulation of lipid-loaded macrophages that have surrounded large amounts of a fatty substance, typically cholesterol, what type of cell is it called? With this lipid accumulation full of macrophages, platelets, smooth muscle cells, collagen & proteoglycans, there is an increase in the tunica intima _, and therefore a decrease in _ size?
tunica intima; “foam cells”; width, lumen
Metarterioles aka? found how often in capillary beds? the flow into a metarteriole is preceded by a _ _?
aka “overflow prevention system”; found w/ALL capillary beds, usually there are multiple metarterioles; preceded by a precapillary sphincter
This “bypass system” is NOT found within all capillary beds? If not found there, where is it typically found?
AVA=arteriovenous anastomosis (AV shunt); found in dermis of skin, stomach wall, & the erectile tissues of penis & clitoris
The overflow prevention system aka? the bypass system aka?
metarterioles; arteriovenous anastomosis (AVA or AV shunt)