According to Selye, there are three stages of reaction to stress conditions. These are namely the alarm reaction stage, the resistance stage, and the exhaustion stage.
The alarm reaction stage is the first stage of stress reactions which includes perception of stress conditions. The hypothalamus sends signals to the associated glands and organs to prepare for the defensive responses.
The adrenal gland receives a signal to secrete the stress hormones while organs such as the liver are signaled to increase the glucose formation which in turn would serve as fuel during stress conditions.
