3. Enteric Nervous System gutgut Central Nervous System (CNS) brainbrain spinal cordspinal cord Peripheral Nervous System (PNS) cranial nerves (12 pr)cranial nerves (12 pr) spinal nerves (31 pr)spinal nerves (31 pr)

4. CNS PNS

5. sensory receptor sensory input integration motor input effector

7. cell body dendrite Synapse axon Myelin sheath

9. Schwann Cells Axon Nodes of Ranvier

10. bipolar eye, ear, & olfactory unipolar multipolar most abundant type in CNS Dorsal root ganglion cells

11. sensory receptors sensory neuron interneuron motor neuron effector

20. Presynaptic neuron Postsynaptic membrane Ca 2+ Synaptic vesicles containing neurotransmitters

23. Acetylcholine- slows heart rate; PNS Glutamate- most prevalent neurotransmitter in the brain Aspartate- in CNS GABA- inhibitory neurotransmitter Glycine- inhibitory neurotransmitter Norepinephrine- awakening from deep sleep Epinephrine- increase heart rate Dopamine- movement of skeletal muscles Seratonin- sensory perception, temp regulation, mood, sleep Nitric oxide- may play a role in memory and learning Enkephalin- inhibit pain impulses by suppressing release of substance P Substance P- enhances perception of pain tyrosine

26. Converging circuit same source Pacinian corpuscles -- pressure different sources control of respiration Diverging Circuit permits broad distribution of a specific input types A. amplification B. divergence into multiple tracts

27. Parallel after-charge circuit several neurons process same information at one time each chain has a different number of synapses, but eventually they all reconverge on a single output output neuron may go on firing for some time after input has ceased important in withdrawal reflexes longer-lasting output from small period of pain

28. Reverberating Circuit axons extend back toward the sources of an impulse and further stimulate the presynaptic neuron helps maintain consciousness, muscular coordination, normal breathing, short term memory...

29. synapses Efferent (motor) Afferent (sensory) Integration center

30. Multiple Sclerosis Autoimmune disease Destruction of myelin sheath Scar tissue may form

31. Epilepsy Rapid synchronous firing of neurons Seizure Treatments: Drugs Implants Brain surgery

32. INQUIRY 1.What voltage is the threshold potential? 2.Describe depolarization, repolarization and hyperpolarization. 3.Which ion causes the neurotransmitters to be released across the synapse? 4.Name 2 instances that you can stimulate a neuron to depolarize. 5.What disease is characterized by myelin sheath degeneration? 6.Can all parts of the CNS regenerate if damaged?