Bipolar plate with media regulation and fuel cell stack

A bipolar plate for a fuel cell is provided having an active region and a marginal region surrounding the active region, and having a first media guide having a first passage and a second media guide having a second passage, and having a media duct extending through the active region and fluidically connecting the first passage to the second passage, wherein the first passage and/or the second passage is associated with a diaphragm, which is adjustable by an actuator to establish or to regulate the flow cross section of the first passage and/or of the second passage. A fuel cell stack having a fuel cell with such a bipolar plate is also provided.