When Susan ran home because a large dog was chasing her, this reaction represents which phase of general adaptation syndrome?

The reaction that Susan experiences when she runs home due to a large dog chasing her exemplifies the alarm phase of general adaptation syndrome. This phase is characterized by the immediate response to a stressor, which is triggered by the perception of a threat. In this case, the sight of the dog creates a sense of danger, prompting Susan's body to activate the fight-or-flight response.

During the alarm phase, biological changes occur, such as an increase in heart rate, heightened awareness, and release of stress hormones like adrenaline. These changes prepare the body to either confront or flee from the threatening situation, which is precisely what Susan does by running home. This instinctive reaction is essential for survival and reflects the body's immediate preparation to handle a perceived danger.

In contrast to the alarm phase, the resistance phase would involve the body's attempts to cope with the stressor after the initial shock has worn off, while the exhaustion phase occurs after prolonged exposure to stress, leading to depletion of resources and reduced ability to cope. The adaptive phase is not a formal part of general adaptation syndrome as described by Hans Selye.