The sa and av nodes are often supplied by both the and arteries.

 The heart receives its blood supply from the coronary arteries. The two main coronary arteries branch off the trunk of aorta close to the aortic va;ve. Coronary arteries receives blood from aorta during diastole when ventricles are resting. Right coronary artery extends to the right  and perfuses the right atrium and right ventricle. The SA node is perfused by RCA in approximately 55% and AV node supplied by RCA in 90% of populatio. The remaining percent is supplied by left circumflex.

The return of the wolf to yellowstone national park will probably affect the bird population to some degree, not significantly. while wolves will hunt birds when necessary, they prefer to hunt larger prey. the bird population will most likely only be affected when hunting is scarce for the wolves. birds of prey will also probably not be affected as much as other birds who spend more time on the ground hunting for food as the tend to spend more time in the air or in trees since they do not need to stay on the ground for long due to the nature of the way they hunt.

Synapse nervous system they process and transmit signals. in a neuron