What hormone is primarily responsible for stress responses?

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

Answer: (C)

Cortisol is primarily responsible for stress responses due to its critical role in the body's fight-or-flight mechanism. When an individual perceives a threat or experiences stress, the hypothalamus triggers the adrenal glands to release cortisol. This hormone mobilizes energy by increasing glucose in the bloodstream, enhancing the brain's use of glucose, and curbing non-essential functions in a crisis situation, such as digestion and immune responses.

Cortisol also modulates various processes to prepare the body for immediate action, including increasing heart rate and blood pressure, and suppressing inflammation. This characteristic makes cortisol vital for helping the body manage prolonged stress effectively, allowing individuals to respond appropriately to challenging situations.

While adrenaline also plays a role in the stress response by providing a quick burst of energy and alertness, it acts more as a short-term response mechanism. Other options like serotonin are primarily involved in mood regulation rather than stress management, and insulin is key in regulating blood sugar levels but does not directly relate to stress responses.