Once an exposure is determined, f/stop and shutter speed are locked together. You can detrmine f/stop, and get a shutter speed to match. Then you can adjust both to get the DoF you want, or a desired shutter speed to stop a moving image or adequate for hand holding the camera.
In the Zone System, the photogrpaher can determine the exposure off of any tone, and expose and process accordingly. The system has historically been applied to B&W negatives. The old advice of expose for the shadow and process for the highlights also works for negatives because developement changes have a much smaller effect on shadows.
Exposing for the highlights is normally used with positive film or digital because over exposed highlights usually look bad while more and deeper shadows can be accepted. Also, color positive films have less latitude in processing techniques without soem adverse color changes. With digital, once the highlight is gone (clipped), nothing will bring it back, but soem shadow detail can be retrieved, provided the exposure is not "black without detail."
A couple of good references on the Zone System are "Zone VI Workshop" by Fred Picker, and the Ansel Adams books on "The Camera," "The Negative," and "The Print."