Matching Pairs Heart EmbryologyOnline version Match the structure with what it gives rise to by Jimmy Jennings 1 primitive atrium 2 primitive ventricle 3 endocardial cushion 4 left horn of sinus venosus 5 right horn of sinus venosus 6 primitive pulmonary vein 7 right common cardinal vein and right anterior cardinal vein 8 truncus arteriosus 9 bulbus cordis atrial septum, membranous interventricular septum coronary sinus atrioventricular node, semilunar valves, trabeculated part of LA and RA trabeculated LV and RV smooth left atrium smooth part of right atrium superior vena cava smooth parts of lv and rv ascending aorta/pulmonary trunk