spread citation through heart Flashcards
identify major structures of heart
look pp
describe path of blood flow through heart
1)ventricles relax, atria contract
2) ventricles contract, atria relax
3)atria and ventricles relax-higher pressure in pulmonary artery and aorta causes semi-lunar valves to close
-atria will fill with blood due to higher pressure in vena cava and pulmonary vein
-ventricles continue to relax, their pressure falls below pressure in atria causes AV valves to open and blood flows passively from ventricles to atria
why quick transmission of heart beats
-quick transmission for rapid contraction
-cardiac cells connected by gap junctions inside interrelated discs
-intercelated discs contain desmosomes which resist mechanical stress
-enables resist stretching as occurs every time heart fills with blood
describe electrocardiograms
vena cava=
from body to heart
aorta=
from heart to body
oxygenated on which side
my left, diagram right
semilunar valve
valve between left ventricle and aorta and right ventricle and pulmonary artery, prevents back flow
ventricular septum=
muscles between ventricles, otherwise oxygenated and does would be mixed
bicsupid/tricuspid valve?
left bicuspid, right triscuspid
gas exchange in pulmonary circuit
O2 moves into blood, CO2 moves out
gas exchange in pulmonary circuit
O2 moves into blood, CO2 moves out
gas exchange in systemic circuit
O2 moves out, CO2 moves into blood
trace path of electrical signal through conduction system of heart
1) impulse at SAN of right atrium, travels to AVN
2)AVN transmits less rapidly, 0.1s delay, down to b8ndle of his
3)AP travel down apex to purkyne fibres
myogenic
heart signals itself
