What physiological changes occur in the body during the 'fight or flight' response?

The correct answer highlights a key aspect of the 'fight or flight' response, which is primarily regulated by the sympathetic nervous system. During this physiological reaction, the body prepares itself to either confront or flee from a threat.

Increased heart rate and respiratory rate are essential adaptations that enable the body to enhance oxygen delivery to muscles and vital organs. When faced with danger, the heart pumps more blood rapidly, allowing for increased oxygen and nutrient supply to essential tissues, particularly those involved in physical activity. Likewise, the respiratory rate elevates to improve oxygen intake, which is crucial for sustaining heightened levels of energy and physical performance.

These changes are adaptive, as they prepare the individual for quick responses to stressors, whether in a direct confrontation or during rapid escape. Thus, this heightened cardiovascular and respiratory activity is a fundamental characteristic of the 'fight or flight' response and illustrates how the body mobilizes resources in times of acute stress.