the heart Flashcards
2 pumps-left and right, which does what
right-blood to lungs
left-blood to everywhere
purpose of valves
prevent the back flow of blood
how valves work
no energy is needed, the lack of pressure of the blood pressing on the valves closes them, when pressure increases valve opens
cardiac cycle
valves closed. blood flows into atria
atria contract, blood pushed into ventricles
ventricles contract, blood into aorta+pulmonary artery
valves open
blood exits heart via arteries
how often does a single cardiac cycle occur
every heart beat
aorta
on left, blood exits via
pulmonary vein
on left, blood enters via
semi-lunar valve
valve between left ventricle and aorta
left atrioventricular valve
valve between left atrium and ventricle
right atrioventricular
valve between right ventricle and right atrium
semi-lunar valve
between right ventricle and pulmonary artery
superior/inferior vena cava
on right, blood enters via
coronary arteries
left and right, stem from aorta supply heart with blood (oxygen and glucose), both are thin
sino-atrial node
group of specialised cells in wall of right atrium. produces regular impulses that spread through atria walls causing contractions
