What hormone increases during stress and prepares the body for 'fight or flight'?

Adrenaline, also known as epinephrine, is the hormone that increases during stress to prepare the body for the 'fight or flight' response. When a person perceives a threat or stressful situation, the adrenal glands, located on top of the kidneys, release adrenaline into the bloodstream. This hormone triggers various physiological changes that enhance the body's ability to respond quickly to the situation at hand.

These changes include an increased heart rate, elevated blood pressure, and enhanced blood flow to muscles, which collectively prepare the body for physical action. Additionally, adrenaline causes the liver to release glucose, providing the necessary energy for rapid movement. This rapid response is critical in situations requiring immediate action, showcasing how the body naturally gears up to deal with perceived threats.

While cortisol, another key hormone that rises during stress, plays an important role in the body's response to stress, it primarily helps with long-term responses and metabolic adjustments rather than the immediate reaction associated with 'fight or flight'. Serotonin and prolactin have different functions and are not directly involved in the body's acute response to stress.