Peripheral Nervous System

Anatomical

Cranial nerves12 nerve bundles

Spinal nervesIntercostal nerves

& 3 plexuses

Divisions

Spinal Nerves

Spinal Nerves have two parts:Dorsal Root

Sensory neurons Receive impulse

Ventral Root Motor neurons Send impulse

Functional

SomaticAssociated with voluntary movement

Distinguished by a single motor neuron from CNS to effector

Autonomic Involves involuntary

changes/reactionsConsists of 2 (or

more) motor neurons from CNS to effector Connect at the a ganglion

Divisions

Parasympathetic Sympathetic

Originate in the brain stem (or sacral region)

Signal to conserve/absorb energy (relaxed/recovery)

Secrete acetylcholine in the post-ganglionic nerve

Originate in the spinal grey matter

Signal to use energy (fight or flight)

Secrete noradrenalin in post-ganglionic nerve

Autonomic Nervous System