Outline the body's response to acute and chronic stress (8)The body has two different responses to stress. The first of these is acute stress, where a system called the sympathomedullary pathway is split into two separate systems involving stress. This involves the autonomic nervous system that splits up into the sympathetic branch and parasympathetic branch. The sympathetic branch ready's the body's system for 'flight or fight', in other words an immediate response, whilst the parasympathetic branch allow the body to come back to normal. The second part of the sympathomedullary pathway is the SAM, or sympathetic adrenal medullary system. This system releases adrenaline, that allows different responses in the body to take place such as an increase on the uptake of oxygen and glucose and suppressing non vital systems such as digestion. As well as this, the ANS (sympathetic branch) releases noradrenaline, that makes the body have an increase in blood pressure and cardiac output. The second of the body's systems that is involved in chronic stress is the PAS or Pituitary Adrenal System. Here the cone shaped part of the brain the hypothalamus plays an important role. The PVN - part of the hypothalamus - produces CRF or corticotrophin releasing factor, which is released into the bloodstream in response to stressors. Once this stressor has reached the pituitary gland, it then stimulates the production of ACTH or adrenocorticotrophic hormone, that is transported to the adrenal glands - in particular the adrenal cortex. The adrenal cortex then produces cortisol, which is responsible for many of the body's immune responses, such as impaired cognitive performance and also a lowered immune system response. This whole system takes about 20 minutes to be activated, and is very efficient at regulating itself.