SpinalCord

Brain

Nerves

• PNS consists of 43 pairs of nerves that transmit info to and from CNS

• 12 pairs of cranial nerves enter the brain directly

• 31 pairs of spinal nerves enter the spinal cord between vertebrae

Skeletal(Somatic)

Sympathetic Parasympathetic

Autonomic

Peripheral Nervous System

• Controls movement of skeletal muscles

• Both voluntary and reflex movements

• Provides sensory information– Sight– Sound– Smell– Taste– Touch

• Two divisions: 1. Sympathetic2. Parasympatheitic

• Controls involuntary functions (glands, organs, blood vessels)– heartbeat– respiration– perspiration– digestion

• Can be influenced by thought and emotion (stress!)

• Defensive “ Fight or flight” response

• Releases adrenaline and noradrenaline

• Increases heart rate and blood pressure

• Increases blood flow to skeletal muscles

• Inhibits digestive functions

CENTRAL NERVOS SYSTEMBrain

Spinalcord

SYMPATHETIC

Dilates pupil

Stimulates salivation

Relaxes bronchi

Accelerates heartbeat

Inhibits activity

Stimulates glucose

Secretion of adrenaline,nonadrenaline

Relaxes bladder

Stimulates ejaculationin male

Sympatheticganglia

Salivaryglands

Lungs

Heart

Stomach

Pancreas

Liver

Adrenalgland

Kidney

• Opposite, “Rest and digest” system

• Calms body to conserve and maintain energy

• Lowers heartbeat, breathing rate, blood pressure

CENTRAL NERVOUS SYSTEMBrain

PARASYMPATHETIC

Spinalcord

Stimulates salivation

Constricts bronchi

Slows heartbeat

Stimulates activity

Contracts bladder

Stimulates erectionof sex organs

Stimulates gallbladder

Gallbladder

Contracts pupil

Autonomic nervous system controls physiological arousal

Sympatheticdivision (arousing)

Parasympatheticdivision (calming)

Pupils dilate EYES Pupils contract

Decreases SALVATION Increases

Perspires SKIN Dries

Increases RESPERATION Decreases

Accelerates HEART Slows

Inhibits DIGESTION Activates

Secrete stresshormones

ADRENALGLANDS

Decrease secretionof stress hormones