Slides in this set
The body's response to stress
Release of Corticotropin-
Adrenal Medulla releasing hormone.
CRH stimulates the
anterior pituitary gland
This then releases
Releases Adrenaline / adrenocorticotropic
Nor Adrenaline hormone.
Stimulates adrenal cortex
Blood pressure and heart
rate, breathing rate,
sweating and muscles AC releases corticosteroids
To convert fat and
Digestion. protein into energy.…read more
1. The Sympathomedullary pathway.
1) In the initial shock response the hypothalamus activates the
sympathetic branch of the autonomic nervous system.
2) This stimulates the adrenal medulla in the adrenal glands,
which releases adrenaline and nor adrenaline into the
3) These effect the body in several ways:
Blood pressure and heart rate increase to get blood quickly to
areas of the body where it's needed for activity.
Digestion decreases so that blood can be directed to the brain and
Muscles become more tense so the body is physically
Sweating increases so the body can cool down and burn more
Breathing rate increases so that more oxygen can be sent to the
The results of these changes is that the body is ready to
use energy to deal with a stressful situation and
prepares the body for `flight or fight'.…read more
2. The Pituitary-adrenal system.
1) If the stress is long term the sympathomedullary
response will start to use up the body's resources. So
the pituitary-adrenal system produces a countershock
response which supplies the body with more fuel.
2) The hypothalamus releases corticotropin-releasing
3) CRH stimulates the anterior pituitary gland which then
releases adrenocorticotropic hormone.
4) ACTH travels through the body and stimulates the
adrenal cortex, which is near the kidneys.
5) The adrenal cortex then releases corticosteroids which
converts fat and protein to give us energy.
6) This energy is needed to replace that used up by the
body's initial reaction to the stress,
e.g. running away.…read more
Hans Selye explained stress as a 3
Hans Selye was researching the effects of hormones on rats
when he noticed rats would become ill and develop
stomach ulcers even when given harmless injections. He
concluded that the stress of the daily injections caused
the illness and that all humans and animals react to
stressors through a 3 stage physiological response. Selye
called this the General Adaptation Syndrome.
1) The Alarm Stage stressor increases arousal levels so
that so that we're ready to make a physical response. E.
g. Run away.
2) The Resistance Stage If the stressor remains for a long
time our bodies can adapt to the situation and appear to
be able to cope in a normal way.
3) The Exhaustion Stage After long term exposure our
bodies will be unable to cope with the situation and we
may develop illnesses. Selye called these `diseases of