Transcript Nervous System

Nervous System
The ANS and Simple
Behaviour Patterns
Nervous System
Nervous System
Nervous System:
 Conscios
activity
controlled by the voluntary (somatic)
nervous system
 Unconscious activity
controlled by the autonomic nervous
system
Autonomic Nervous
System
Autonomic Nervous System
Sympathetic
Parasympathe
System
tic
The motor neurones
secrete noradrenaline
at the synapse
The motor neurounes
secrete acetylcholine
at the synapse
Sympathetic
Causes the “fight or flight”
 Divert blood from the gut to the lungs, heart
and voluntary muscle
 Increase supply to the muscles
 The lungs absorb more oxygen
 More blood available for the heart and lungs
Parasympatheic
 Prepare
the body for rest
 Decrease heart beat rate
 Decrease ventilation rate
 Increase peristalsis in the gut, food can be
digested
Comparison of the sympathetic and
parasympathetic nerovs systems
Feature
Transmitter
substance at
synapses
Heart rate
Iris
movements of
digestive tract
Sweating
Sysmpathetic
Parasympathetic
Noradrenaline
Acetylcholine
Speeds up
Slows down
Dilates
Constricts
Slows down
Speeds up
Stimulated
Not stimulated
Heart Beat
Affect on heart rate
 Sympathetic
nerves increase the rate of
cardiac muscle contraction
 Parasympathetic nerves relax muscles
ANS
1.
2.
3.
4.
5.
6.
7.
Blood stretches the
baroreceptors
Action potential sent
Impulse send along the
motor vagus nerve
SAN slow the rate
Blood put pressure
Bainbridge reflex
Baroreceptors control the
pressure of blood flowing
to the head