SOMATIC NERVOUS SYSTEM (SNS)

Sensory neurons convey information from cutaneous and special sense organs, body wall and limbs to the CNS

Motor neurons that conduct impulses from CNS to skeletal muscle only

"voluntary"

AUTONOMIC NERVOUS SYSTEM (ANS)

Sensory neurons convey information from receptors in viscera to CNS

Motor neurons that conduct impulses to smooth muscle, cardiac muscle and glands

"involuntary"

BRANCHES OF ANS

Sympathetic

involves expenditure of energy

Parasympathetic

restores or conserves energy

ANS BRANCHES

two divisions have opposing actions

ex: sympathetic speed up heart rate

parasympathetic slows down heart rate

NERVE TYPES

1) neurons

sense think remember regulate gland function control muscle movement

2) neuroglia

support neurons nurture neurons protect neurons

NEUROGLIA

"glia cells" Support neurons More numerous than neurons Make up half the mass of the brain Able to multiply and divide Multiply and fill in areas of neurons that are destroyed by injury Brain tumors commonly arise from glia cells and are highly malignant

NEUROGLIA TYPES