Answer to Question 1
Eventually, negative stressors can have an impact on life expectancy itself. Unhealthy behaviors and lifestyles, many related to stress, are believed to account for many premature deaths. For instance, in the United States smoking tobacco causes approximately 80 of the lung cancer deaths for women and 90 for men. This is the bad news. The good news, however, at least in many parts of the world, is that people today who live healthy lifestyles can generally expect to live a long life.
Answer to Question 2
Physiological reactions to stressors typically involve not only the central nervous system, but also the immune system, the autonomic nervous system, and the endocrine system. These reactions may include heart rate increases, blood pressure elevation, muscle tension, dry throat and mouth, trembling, teeth grinding, cold hands and feet, headaches, weakness, fatigue, and frequent illnesses. Changes due to stressors typically have negative effects on our relationships and on our work performance. Behavioral changes such as frequent arguing, poor work performance, overeating or under-eating, and others usually set up vicious cycles that amplify stress reactions.
negative feedback loop
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