cardiovascular - lecture 4 Flashcards
what is pulmonary circualtion?
supplies blood to lungs for exchange of O2 and CO2
what is systemic circulation?
supplies blood to organs to provide O2 and nutrients
what is the difference between arteries and viens?
arteries move away from heart, have high pressure, thicker walls, and no valves
veins move toward heart, have low pressure, thin walls, and some valves
what is tunica intima?
inner layer of vascular system, has endothelial lining and underlying connective tissue with elastic membrane
what does the tunica intima do?
regulates blood flow and vessel size
what is the tunia media?
middle layer of arteries concentric sheets of smooth muscle in loose connective tissue with elastic membrane
what does the tunica media do?
mechanical strength, regulates flow and size, dilation/constriction
what is the tunica externa?
outer layer of vascualar system, connective tissue sheath, anchors vessel to adjacent tissues, has collagen and elastic fibres and smooth vessel
what does the tunica externa do?
holds vessel in place
what is the difference between vein layers and artery layers?
veins have a thinner tunica media
what does the aorta do?
pulse dampening and distribution
what do the large arteries do?
distribute arterial blood
what do the small arteries do?
distribution and resistance
what do arterioles do?
resistance
what do the capillaries do?
gas exchange
what do the venules do?
gas exchange, collection, capicitance
what do veins do?
capacitance
what does the vena cava do?
collection
how do you calculate blood flow?
pressure gradient (△P) / resistance (R)
what is blood pressure?
force per unit area exerted on wall of blood vessel by contained blood
what is systolic blood pressure?
amount of pressure on blood vessels when ventricles contract
what is diastolic blood pressure?
amount of pressure on blood vessels when the heart is at rest between contractions
what is normal systolic BP?
less than 120 mmHg
what is normal diastolic BP?
less than 80 mmHg
