PHGY 214 Lecture Notes - Lecture 31: Hyperthyroidism, Cardiac Output, Viscosity
9 Dec 2017
School
Department
Course
Professor
Document Summary
Arteries: serve as rapid transit passageway for blood from heart to organs, large radius= little resistance to blood flow. Act as pressure reservoir to provide additional driving force for blood when heart is relaxing: gain additional force by being elastic recoil, elastic property allows for cont flow of blood (windkessel effect) Arterial ct contains: collagen fibers for tensile strength and elastin for elasticity. Tunica intima: subendothelial layer, grows w age or disease conditions. Both ct and smooth muscle are present in intima, border of intima is delineated by internal elastic memb which may be hard to see due to large amounts of elastic material in tunica media. Tunica media: this is the thickest of the three layers. The smooth muscle cells are arranged in a spiral around the long axis of the vessel. They secrete elastin in the form of sheets, or lamellae, which are fenestrated to facilitate diffusion.
