epicardium
serous membrane on the surface of the myocardium
myocardium
heart muscle; forms the walls of the four chambers
endocardium
endothelium that lines the chambers and covers the valves; smooth to prevent abnormal clotting
right atrium (RA)
receives deoxygenated blood from the body by way of the superior and inferior caval veins
tricuspid valve
right AV valve; prevents backflow of blood from the RV to the RA when the RV contracts
right ventricle (RV)
pumps blood to the lungs by way of the pulmonary artery
pulmonary semilunar valve
prevents backflow of blood from the pulmonary artery to the RV when the RV relaxes
left atrium (LA)
receives oxygenated blood from the lungs by way of the four pulmonary veins
mitral valve
left AV valve; prevents backflow of blood from the LV to the LA when the LV contracts.
left ventricle (LV)
pumps blood to the body by way of the aorta
aortic semilunar valve
prevents backflow of blood from the aorta to the LV when the LV relaxes
papillary muscles and chordae tendineae
in both the RV and LV; prevent inversion of the AV valves when the ventricles contract.