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