The fight or flight response is associated with the release of adrenaline and stress hormones such as cortisol. The release of adrenaline is responsible for the increase in heart rate, widening of the air sacs in the lungs, and the increase in blood pressure. Cortisol is responsible for the suppression of the immune system and the increase in glucose production. The fight or flight response and the cascade of effects that leads to the release of adrenaline and cortisol is illustrated in the following flowchart:
