Stress - an inbalance between perceived demands and percieved ability to cope
Stressor - a physical or psychological stumlus which threatens an indiviual pyscological or well being . Anything percieved as a threat which arouses fear or anxiety grief. Stressors differ between indiviual and time.
Stress Response - an innate, defensive reaction to promote survival e.g flight or fight. However not all stress situations result in response influenced by the individuals physical + mental condition, age,sex, hereditary with similar stressor.
On way the body repsonds to stress is the sympathoadrenomedullary response (SAM), in this the hypothalamus percieves a stressor and activates the sympathtic branch of the ANS. this stimulates the adrenal medulla to produce adrenaline which in turn increases heart rate, depth and rate of respiration, diverts blood to the major muscle groups.
A second way the body responds to stress is through activating the hypothalamic PA axis (HPA) The hypothalamus recieves a stressor and activates the piturity gland to release ACTH. This acts on the adrenal cortex and glucocorticoids such as cortisol are released. These aid with response to injury and inflammation. Also glucose stores in ther liver are released for more energy.