Final answer:
The general adaptation syndrome is a three-stage process theorized by Hans Selye, explaining the body's physiological reaction to stress, including the stages of alarm reaction, resistance, and exhaustion which can lead to significant health problems if prolonged.
Step-by-step explanation:
The general adaptation syndrome (GAS) is a three-stage process that describes the physiological changes the body goes through when under stress. GAS was conceptualized by Hans Selye and includes the following stages: alarm reaction, stage of resistance, and stage of exhaustion.
During the alarm reaction stage, immediate reactions to a stressor activate the body's fight-or-flight response, which is characterized by the secretion of hormones like epinephrine and norepinephrine to prepare the body for quick action. If the stress continues, the body enters the stage of resistance. Here, physiological adjustments are made to cope with the stressor, like maximizing nutrient absorption if starving. However, if the stress persists for a prolonged period, the individual reaches the stage of exhaustion, in which the body's resources are depleted, leading to potential health issues such as hypertension and coronary artery disease.