Vasculature 1 Flashcards
Main modes of transport in CV system are
Bulk flow
-blood is moved through vessels rapidly over long distances
-requires energy- provided by pressure difference (see below)
Diffusion -driving force is concentration gradient
-moves substances across blood vessel walls to interstitial fluid
-interstitial fluid is ECF outside capillaries
Pulmonary and systemic circulation are arranged in? Various organs within the systemic circulation are arranged in?
Series
Parallel
Central circulation
pulmonary plus cardiac circulation
Coronary circulation
blood supply to the heart muscle
Portal systems in the body include?
Two capillary beds arranged in series
Hepatic protal system (splanhnic circ–> liver)
Renal portal system (glomerulus –>tubules)
Hypophyseal portal system(hypothalamus–> anterior pit)
As move from aorta to capillaries
vessel number increases diameter decreases total cross sectional area increases velocity of blood flow decreases mean blood pressure decreases
Velocity of blood flow drops quickly from arterioles to capillaries due to?
Branching
-very large SA due to large cross-sectional area
Perfusion pressure
pressure difference between inlet (aorta) and outlet (vena cave) of tube drives fluid forward
Perfusion pressure is created by?
heart pumping
Conduit vessel=?
vessel that offers little resistance
Compliance vessels=?
less resistance to flow than arterioles
Compliance=?
change in blood volume in a vessel in association with a change in distending pressure
compliance= delta volume/delta distending pressure
Poiseuille’s law
resistance = perfusion pressure difference/flow
-resistance is inversely related to tube radius but directly proportional to viscosity and length
Vascular resistance
vasoconstriction-increase resistance and decrease blood flow
vasodilation- decreased resistance and increased blood flow
In severe hemorrhage or dehydration CO is? TRP is?
CO is reduced due to reduced venous blood to heart (aka preload)
TPR is eleveated in these situations
