Showing all that on one slide:

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Showing all that on one slide

• The Hypothalamus secretes CRH (Corticotrophin-rel
  easing hormone).
• CRH causes the Pituitary Gland to secrete ACTH
  (adrenocorticotrophic hormone).
• ACTH causes the Adrenal Cortex to secrete
  corticosteroids, which is carried in white blood
  cells to reduce inflammation and to combat
  allergic reactions.
• ACTH also causes the Adrenal Medulla (lower part
  of adrenal cortex) to release a mixture of
  adrenaline and noradrenaline, which arouses the
  body by accelerating the heart rate causes the
  liver to release glucose (sugar). This provides
  the energy for the fight-or-flight reaction.

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• Resistance Stage The body tries to cope with the
  specific stressor by focusing its resources on
  the particular stressor. (Also called Adaptation
  Stage)

Resistance Stage cont..There is prolonged
endocrine sympathetic activity at lower levels,
which are still higher than normal

• Exhaustion Stage..The body can no longer control
  the effects of stress and begins to break down.
  (illness, headaches, nervous, fatigue)The
  parasympathetic nervous system is activated
  works to reverse sympathetic processes

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Exhaustion Stage (cont)
Exhaustion Stage (cont)
But the stressor is still present, and possibly
it is an external danger the body is still under
stress. (War, disease, wild animal)
Continued stress in the exhaustion stage may
lead to diseases of adaptation (Selye)
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Effects of Stress on the Immune System
The system produces leukocytes (white blood
cells) to engulf kill pathogens (antigens) such
as bacteria, fungi, and viruses.
We build antibodies (proteins) to fight them and
remember them.
Inflammation
When injury occurs, blood vessels first contract
to stem bleeding, and then they dilate to
increase blood flow to the damaged area for
healing. This also brings the leukocytes to
protect against outside invaders.
Immune System (cont)
A factor in exhaustion is that continued stress
causes the body to persistently secrete steroids,
which suppress the immune functions discussed.
This makes us more
vulnerable to illness