double-walled sac (visceral + parietal)
Outer lining of the heart
Layer of the heart which is composed mainly of cardiac muscle and forms bulk of heart.
It is the layer that contracts
glistening white sheet of endothelium.
Located in the inner myocardial surface.
Lines the heart chambers + covers the valves
Chamber of heart that separates atria and ventricles
piece of tissue which creates the valves
"heart strings" which anchor cusps to papillary muscles
prevents valves from opening by swinging backwards (inversion of the valves)
Contraction of the heart. Blood flows out of the heart
Semilunar Valves open, AV valves close
Relaxation of the heart. Blood flows into the heart
AV valves open, Semilunar valves close
pacemaker of the heart. Generates the most impulses, most Na+ flowing in
impulses pause here for a fraction of a second. (.1s)
Bundle of His
projects from the AV node. Connects the atria to the ventricles
depolarize the contractile cells of both ventricles
A graphic record of heart activity
depolarization of the atria. atria contracts. Systole
depolarization of ventricles. Late Diastole. ah