1 / 34

The Nervous System

The Nervous System. Protection of the Central Nervous System. Scalp and skin. Protection of the Central Nervous System. Figure 7.17a. Meninges. Dura mater Double-layered external covering Periosteum — Meningeal Layer- Folds inward in several areas. Meninges. Arachnoid layer

tatiana-hopkins
Download Presentation

The Nervous System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Nervous System

  2. Protection of the Central Nervous System • Scalp and skin

  3. Protection of the Central Nervous System Figure 7.17a

  4. Meninges • Dura mater • Double-layered external covering • Periosteum— • MeningealLayer- • Folds inward in several areas

  5. Meninges • Arachnoid layer • Pia mater

  6. Meninges Figure 7.17b

  7. Cerebrospinal Fluid (CSF) • Similar to blood plasma composition • Formed by the choroid plexus • Forms a watery cushion to protect the brain • Circulated in arachnoid space, ventricles, and central canal of the spinal cord

  8. Ventricles and Location of the Cerebrospinal Fluid Figure 7.18a–b

  9. Ventricles and Location of the Cerebrospinal Fluid Figure 7.18c

  10. Hydrocephalus in a Newborn • Hydrocephalus Figure 7.19

  11. Blood-Brain Barrier • Includes the least permeable capillaries of the body • Excludes many potentially harmful substances • Useless as a barrier against some substances

  12. Traumatic Brain Injuries • Concussion • Contusion • Cerebral edema

  13. Cerebrovascular Accident (CVA) • Commonly called a stroke • The result of a ruptured blood vessel supplying a region of the brain • Brain tissue supplied with oxygen from that blood source dies

  14. Alzheimer’s Disease • Progressive degenerative brain disease • Mostly seen in the elderly, but may begin in middle age • Structural changes in the brain include abnormal protein deposits and twisted fibers within neurons

  15. Spinal Cord • Extends from the foramen magnum of the skull to the first or second lumbar vertebra

  16. Spinal Cord Anatomy Figure 7.20 (1 of 2)

  17. Spinal Cord Anatomy Figure 7.20 (2 of 2)

  18. Spinal Cord Anatomy • Internal gray matter is mostly cell bodies • Dorsal (posterior) horns • Anterior (ventral) horns • Gray matter surrounds the central canal • Exterior white mater—conduction tracts

  19. Spinal Cord Anatomy Figure 7.21

  20. Spinal Cord Anatomy • Meninges cover the spinal cord • Spinal nerves leave at the level of each vertebrae • Dorsal root • Ventral root

  21. Pathways Between Brain and Spinal Cord Figure 7.22

  22. Peripheral Nervous System (PNS) • Nerves and ganglia outside the central nervous system • Nerve

  23. PNS: Structure of a Nerve • Endoneurium surrounds each fiber • Groups of fibers are bound into fascicles by perineurium • Fascicles

  24. PNS: Structure of a Nerve Figure 7.23

  25. PNS: Classification of Nerves • Mixed nerves • Sensory (afferent) nerves • Motor (efferent) nerves

  26. PNS: Cranial Nerves • 12 pairs of nerves that mostly serve the head and neck • Only the pair of vagus nerves extend to thoracic and abdominal cavities

  27. PNS: Cranial Nerves • I Olfactory • II Optic • III Oculomotornerve • IV Trochlear

  28. PNS: Cranial Nerves • V Trigeminal • VI Abducens • VII Facial • VIII Vestibulocochlear

  29. PNS: Cranial Nerves • IX Glossopharyngeal nerve— • X Vagus nerves— • XI Accessory nerve— • XII Hypoglossal

  30. PNS: The Cranial Nerves Table 7.1 (1 of 4)

  31. PNS: The Cranial Nerves Table 7.1 (2 of 4)

  32. PNS: The Cranial Nerves Table 7.1 (3 of 4)

  33. PNS: The Cranial Nerves Table 7.1 (4 of 4)

  34. PNS: Distribution of Cranial Nerves Figure 7.24

More Related