Advanced Placement (AP) Biology Practice Exam

In which situations is epinephrine mainly secreted?

1. During periods of rest

2. During exercise

3. In conditions of stress

4. During digestion

The correct answer is: In conditions of stress

Epinephrine, also known as adrenaline, is primarily secreted during conditions of stress. This hormone plays a key role in the body's fight-or-flight response, which is activated in reaction to stressful or threatening situations. When an individual perceives a potential danger or experiences extreme stress, the adrenal glands release epinephrine into the bloodstream. This leads to physiological changes like increased heart rate, heightened blood pressure, enhanced energy availability, and improved airflow to the lungs, all of which prepare the body to respond effectively to the stressor. The secretion of epinephrine is not typically associated with periods of rest, exercise, or digestion in the same way it is during stress. While exercise can increase the release of epinephrine to some extent, particularly during high-intensity activity, the primary triggers for significant secretion are acute stress events rather than regular physical activity or metabolic processes like digestion.