Final answer:
A) Hormone secretion In stressful situations, the body secretes hormones leading to an increase in heart rate and a general elevation in physiological activity as part of the 'fight-or-flight' response.
Step-by-step explanation:
When a stressful situation is encountered, the body's response includes hormone secretion. This is part of the 'fight-or-flight' reaction, a complex physiological and behavioral set of responses designed to deal with threatening situations. The sympathetic nervous system is activated, resulting in increase in heart rate and accelerated respiration.
Hormones like adrenaline and cortisol are released, raising the heart rate, blood sugar levels, and influencing many other changes to prepare the body to either confront the danger or escape from it. Contrary to slowing down, these responses generally cause an increase in physiological activity to prepare for quick action.
When a threat or danger is perceived, the body responds by releasing hormones that will ready it for the 'fight-or-flight' response. This includes increased heart rate, dry mouth, and hair standing up. In response to stress, the sympathetic nervous system triggers arousal via the release of adrenaline,
while the hypothalamic-pituitary-adrenal (HPA) axis becomes active and releases cortisol, known as a stress hormone. Sustained elevated levels of cortisol weaken the immune system.