Could you explain the physiological basis of the body’s response to stress

Could you explain the physiological basis of the body’s response to stress, commonly known as the fight-or-flight response? How does the activation of the sympathetic nervous system lead to the release of stress hormones like adrenaline and cortisol, resulting in increased heart rate, blood pressure, and respiratory rate? Furthermore, how does chronic stress impact various physiological systems, including the immune, cardiovascular, and gastrointestinal systems?