Watch this video if you want to learn about the development of heart with the help of labeled animations with smooth transitions and a very refreshing background music. Timeline: 0:00 - Primitive heart tube formation 1:03 - Primitive heart tube folding and looping 2:39 - Secondary heart field contributions 3:15 - Atrioventricular canal partitioning and and formation of endocardial cushion tissue 3:58 - Heart tube chambers realignment 4:42 - AV canal subdivision 4:56 - AV valves formation 5:25 - Partitioning of the atrium 6:27 - Partitioning of the ventricles 6:54 - Partitioning of the outflow tract 8:20 - Partitioning of aortic sac 8:36 - Semi-lunar valves formation 9:26 - Membranous interventricular septum formation