Which hormone is responsible for the body's fight or flight response?

• A. Cortisol
• B. Adrenaline
• C. Prolactin
• D. Insulin

Answer: (B)

Adrenaline, also known as epinephrine, is the primary hormone responsible for the body's fight or flight response. When a person faces a perceived threat, the adrenal glands release adrenaline into the bloodstream, initiating a series of physiological changes to prepare the body for rapid action. These changes include increased heart rate, enhanced lung capacity, redistribution of blood flow to essential muscles, and heightened awareness. This response allows individuals to react quickly to dangerous situations.

Cortisol, while also involved in stress responses, primarily helps regulate metabolism and immune response over a longer duration rather than the immediate reaction seen with adrenaline. Prolactin is mainly associated with lactation and reproductive functions, having no direct role in the fight or flight response. Insulin's primary function involves regulating blood sugar levels and does not play a role in immediate physical response to stress or danger. Thus, adrenaline is uniquely suited to facilitate quick and effective reactions necessary for survival in high-stress situations.