part of part of in taxon results in development of cardiac conduction system development sinoatrial node development GO:0003163 dph SA node development 2009-10-01T02:06:09Z The process whose specific outcome is the progression of the sinoatrial (SA) node over time, from its formation to the mature structure. The SA node is part of the cardiac conduction system that controls the timing of heart muscle contraction. It relays electrical signals to the AV node. sinus node development SAN development atrial cardiac muscle tissue development anatomical structure development Vertebrata <vertebrates> sinoatrial node