Which hormone is associated with the sympathetic stress response?

The correct answer is associated with adrenaline, also known as epinephrine, which is a key hormone in the sympathetic stress response. When an individual perceives a stressor, the body activates the 'fight or flight' system, leading to the release of adrenaline from the adrenal glands. This hormone prepares the body to react quickly to perceived threats by increasing heart rate, enhancing energy production, and redirecting blood flow to essential muscles while inhibiting non-essential functions, such as digestion.

Cortisol, while also involved in the stress response, plays a secondary role compared to adrenaline. It is a glucocorticoid hormone released later in response to prolonged stress, helping to regulate metabolism and immune responses rather than providing the immediate reactions necessary for acute stress.

Serotonin primarily functions as a neurotransmitter that regulates mood, appetite, and sleep, and is not directly involved in the acute stress response characterized by adrenaline release.

Insulin is a hormone that regulates blood glucose levels and does not have a direct role in the sympathetic stress response, making it unrelated to immediate responses to stressors.

Thus, adrenaline is the primary hormone associated with the immediate effects of the sympathetic nervous system during stress.