Transcript Sympathetic and parasympathetic branches

Autonomic nervous system
•Controls body activities automatically
(involuntary nervous system; regulated
by areas of the hypothalamus and
brain stem)
•Very important for homeostasis
•Controls cardiac muscle, smooth muscle,
and glands, etc.
Ex: heart rate, blood pressure, breathing
rate, stomach secretion amount
Sympathetic and parasympathetic
branches:
2 subdivisions of the motor part of the
autonomic nervous system
(motor = from brain)
A quick overview
• Serve same
organs
• Cause “opposite”
effects
Sympathetic
“fight or flight”
• involved when scared, excited, or exercising
• Ex:
–
–
–
–
–
Increased heart rate and respiratory rate
cold/sweaty skin
dilated pupils
constriction of blood vessels to the digestive system (less blood)
dilation of blood vessels to skeletal muscles and cardiac muscle
• Prolonged sympathetic nervous system activity can lead
to health problems
– Type A personalities
Parasympathetic nervous system
• “rest and digest”
• Conserve and
restore energy
• SUDD
– Salivation
– Urination
– Digestion
– Defecation
“3 decreases”
-- Heart rate
-- Diameter of
airways
-- Diameter of pupils
Sympathetic
parasympathetic
Digestive sys. ___ activity
____ activity
Heart
____ rate
____ rate
Respiratory
airways
_____
diameter
____ diameter
Eye
___ pupils
____ pupils
Adrenal
glands
Secrete
“adrenaline”