Assertion: artery's layer | /r/HasProperty | collagen fibers
Facets:
value: mainly
type: DEGREE
value: with the largest arteries
type: OTHER
Source sentences:
text: The outermost layer of an artery (or vein) is known as the tunica externa, also known as tunica adventitia, and is composed of collagen fibers and elastic tissue - with the largest arteries containing vasa vasorum (small blood vessels that supply large blood vessels).
text: The outer layer of a blood vessel wall, the, is mainly composed of collagen fibers that protect and reinforce the vessel, and anchor it to surrounding structures.