The document discusses the peripheral nervous system, including: 1. Sensory receptors and motor endings in the extremities, as well as the cranial nerves and four main plexuses. 2. Reflexes require stimulus, sensory information, central processing, motor activation, and a peripheral response. 3. Peripheral sensory receptors include free nerve endings and encapsulated endings that detect stimuli like touch, pressure, and proprioception. 4. Motor endings similarly to synapses activate skeletal muscle, smooth muscle and glands. 5. Cranial nerves originate and terminate in specific brain regions, carrying sensory and motor fibers.

1. Ch 14: Peripheral Nervous System Sensory Receptors Motor Endings Cranial Nerves The Four Plexuses Extremities

8. Peripheral Nerves (repetitio est…) Definition: bundles of axons. AKA tracts in CNS Organization – coverings (chapter 12): Epineurium – wraps entire nerve Perineurium – wraps fascicles of tracts Endoneurium - wraps individual axons Function: sensory - afferent motor - efferent mixed - contains axons of both

9. Anatomy of a Peripheral Nerve

15. Trochlear Nerve (N IV) Oculomotor (N III) Lateral view

17. Abducens (CN VI) C : Motor O : Pons D : Lateral rectus eye muscle

19. Facial (CN VII), cont’d Bell’s Palsy

21. Vestibulocochlear (CN VIII)

22. Glossopharyngeal (CN IX) C : mixed O : sensory from posterior 1/3 of tongue / motor from medulla oblongata D : medulla / muscles for swallowing, parotid gland

26. N XII N XI

27. Mnemonics Out On Our Table Top Are Fruits, Very Green Veggies And Hamburgers Oh, Once One Takes The Anatomy Final, Very Good Vacations Appear Heavenly

30. Cervical Plexus Phrenic nerve - innervates diaphragm

31. Brachial Plexus

32. Nerves of the Arm Musculocutaneous nerve – innervates biceps and brachialis muscles Median nerve - innervates lateral flexors Ulnar nerve - innervates medial flexors Radial nerve - innervates forearm extensors

33. Lumbar Plexus Femoral Nerve Lumbosacral Trunk (to Sciatic Nerve) Obturator Nerve

34. Sacral Plexus

36. Narrow lumbar disk spaces result in pressure on the spinal roots L-5 T-12

37. The white oval is a postsurgical cyst or abscess