EXAM 2 Starts: Circulatory System Flashcards
what is the primary function of the circulatory system
transport of O2, CO2 and nutrients/ metabolic waste
what are the secondary functions of the circulatory system
thermoregulation, transport of immune cells/hormones
what does the blood vascular system consist of
heart and blood vessels
what are the two components of the circulatory system
pulmonary circulation and systemic circulation
what is pulmonary circulation
RA -> RV ->pulmonary artery -> lungs -> pulmonary veins -> LA
what is the systemic circulation
LA -> LV -> aorta -> rest of body
what is the lymph vascular system
passive drainage system for returning extravascular fluid (lymph) to blood vascular system
what does the lymph vascular system rely on and why
muscle contractions and body movement because it lacks an intrinsic pump
what are vascular tunics
blood vessels of the circulatory system have common basic structure with 3 concentric layers
what are the 3 vascular tunics from innermost to outermost
- tunia intimia
-tunica media - tunia adeventitia
what is the tunica intima, what type of epithelia, and how thick
innermost layer of simple squamous endothelial cells lining the lumen. very thin 1-2 cells thick
what is the function of the tunica intima
forms a semi-permeable barrier supported by the basement membrane
what are the tight junctions between endothelial cells in the tunica intima called
fascia occludens
what supports the tunica intima
subendothelial connective tissue
where is the internal elastic lamina
separates the tunica intima from the tunica media
what is the internal elastic lamina made of
elastic fibers arranged in an sin wave pattern
what is the tunica media
middle layer made of smooth muscle and fibroblastic connective tissue
what is the thickest layer in arteries and what do arteries contain
tunica media
- may contain reticulin (type 3 collagen) and elastic fibers
where is the external elastic lamina located
between tunica media and adventitia
what is the external elastic lamina composed of
elastic fibers but less organized than internal elastic lamina
what is the tunica adventitia and what does it contain
outermost layer made of loose fibroblastic CT, fibroblasts, collagen, elastic fibers and smooth muscle cells
what is the thinner layer in the arteries
tunica adventitia
what is the thickest layer in veins
tunica adventitia
what are vasa vasorum and where are they located
they are small blood vessels that supply the tunica media and adventitia in both large arteries and veins