So the autonomic nervous system can basically control the blood pressure and the blood flow through our arteries. And that's important in our body. Now, finally, it also has a high resistance to blood flow because as soon as that blood enters our artery, it wants to recoil back into place. And so that creates a high resistance. And that's exactly why the ventricles of our heart have to create such a strong force, such a high hydrostatic pressure to move all that blood through these arteries that have a relatively high resistance. So when the ventricles contract, they fill our blood vessels, they fill the arteries.