Circulatory System Flashcards
Define a double circulatory system
blood passes through the heart twice and has two different circuits
what is the function of valves
to prevent backflow of blood
where are pacemakers found
right atrium
what are pacemakers
small electrical impulses which regulate the rate of contraction
the order of bloodflow through the heart:
vena cava, right atrium, right ventrical, pulmonary artery, lungs, pulmonary vein, left atrium, left ventricle, aorta
coronary arteries
encircle the heart to ensure that muscle cells get all nutrients and oxygen needed
arteries carry blood…
away from the heart
veins carry blood…
towards the heart
capillaries exchange…
nutrients and oxygen with tissues
arteries have thick layers of muscle/elastic tissue in order to…
deal with the high pressure blood which flows through them
arteries have a small lumen so that…
high blood pressure is maintained
capillaries take away…
waste products like CO2
capillaries are one cell thick and permeable in order to…
allow for the diffusion of substances into and out of the capillaries to cells
the cross sectional area of capillaries is huge in order to…
allow bloodflow to run slower and give capillaries more time to exchange substances
veins have large lumens and thin walls because…
blood is low pressure
