2. Spinal Cord 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

3. Skeletal (Somatic) SympatheticParasympathetic Autonomic Peripheral Nervous System

4. Controls movement of skeletal muscles Both voluntary and reflex movements Provides sensory information –Sight –Sound –Smell –Taste –Touch

5. Two divisions: 1.Sympathetic 2.Parasympatheitic Controls involuntary functions (glands, organs, blood vessels) –heartbeat –respiration –perspiration –digestion Can be influenced by thought and emotion (stress!)

6. 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 SYSTEM Brain Spinal cord SYMPATHETIC Dilates pupil Stimulates salivation Relaxes bronchi Accelerates heartbeat Inhibits activity Stimulates glucose Secretion of adrenaline, nonadrenaline Relaxes bladder Stimulates ejaculation in male Sympathetic ganglia Salivary glands Lungs Heart Stomach Pancreas Liver Adrenal gland Kidney

7. Opposite, “Rest and digest” system Calms body to conserve and maintain energy Lowers heartbeat, breathing rate, blood pressure CENTRAL NERVOUS SYSTEM Brain PARASYMPATHETIC Spinal cord Stimulates salivation Constricts bronchi Slows heartbeat Stimulates activity Contracts bladder Stimulates erection of sex organs Stimulates gallbladder Gallbladder Contracts pupil

8. Autonomic nervous system controls physiological arousal Sympathetic division (arousing) Parasympathetic division (calming) Pupils dilate EYES Pupils contract Decreases SALVATION Increases Perspires SKIN Dries Increases RESPERATION Decreases Accelerates HEART Slows Inhibits DIGESTION Activates Secrete stress hormones ADRENAL GLANDS Decrease secretion of stress hormones