1. NUTS AND BOLTS to get started

2. Planes of orientation

3. Confusing terms (Particularly where the CNS makes its’ 90 degree bend) Anterior-Posterior/Rostral-Caudal Dorsal-ventral/ Superior-inferior

4. Dorsal fins

8. The basic unit of the nervous system

9. Myelin gives a whitish appearance because its adipose content Shwann cells myelinate the PNS

10. Oligodendrocytes myelinate the CNS

11. White matter and gray matter reflect organization

12. Staining for myelin in the brain coronal section

13. Myelin Staining in the Spinal cord Horizontal plane Dorsal ventral

14. Organizational schemes always have shortcomings: The PNS can not be truly separated from the CNS

15. To consider the PNS we first must consider the spinal cord The vertebral column

18. Each vertebra houses a spinal cord segment Midsaggital view

19. Each segment is similar: Central gray and surrounding white matter

22. Central gray: Dorsal = sensory Ventral = motor

23. Each segment gives rise to nerve pairs: i.e. The PNS

24. 31 peripheral nerve pairs

25. Each nerve pair contains thousands of incoming and outgoing axons

27. The PNS :All neural tissue outside of the cranium and vertebral column ( with one exception)

28. Major divisions of the PNS

30. motor output to skeletal muscles

31. And somatosensory input

33. The somatic division of the PNS gives rise to segmental organiztion: Dermatomes and myotomes

35. The autonomic division

36. The other subdivision of the PNS- the ANS

37. The sympathetic chain

38. Sympathetic activation may be magnified by adrenal gland

39. Some functional differences between the somatic branch and the ANS

40. THE CNS

41. Exception- The cranial nerves