AEMCA Practice Exam

How does epinephrine function in the body?

1. It inhibits the response of the immune system

2. It stimulates the flight or fight reaction

3. It acts as a sedative for anxiety

4. It dilates blood vessels only

The correct answer is: It stimulates the flight or fight reaction

Epinephrine, also known as adrenaline, plays a crucial role in the body's response to stress or perceived danger, commonly referred to as the "fight or flight" response. When released from the adrenal glands, epinephrine activates several physiological responses that prepare the body to handle emergencies. This includes increasing heart rate, enhancing blood flow to muscles, dilating airways for improved oxygen intake, and mobilizing energy stores. These changes collectively equip an individual to either confront or escape from a threatening situation, highlighting the importance of epinephrine in survival. The other options do not accurately represent the primary role of epinephrine. While it may influence the immune response, it is not explicitly inhibiting it. Instead, epinephrine primarily aims to enhance physical performance under stress. It does not function as a sedative; in fact, it tends to induce a state of alertness rather than relaxation. Finally, while epinephrine does promote the dilation of some blood vessels, this effect is not limited to that function alone; it has a broader range of actions that are vital for the fight or flight response.