The Peripheral Nervous System (PNS)

							   The Peripheral Nervous
       System (PNS)
31 pairs of spinal nerves and 12 cranial nerves
                outside the CNS
I. Spinal Nerves
Lead to and from the spinal cord
Plexuses- “braid”, cluster of nerves
   except T2-T12
     I. Spinal Nerves
A. Cervical / brachial plexus- 8 nerves
     around the 7 cervical vertebrae
B.   Thoracic- 12 nerves around 12 thoracic
     vertebrae; not a plexus
C.   Lumbar- 5 nerves around 5 lumbar
     vertebrae; cauda equina- horse tail
     appearance
D.   Sacral plexus- 5 nerves around sacrum
E.   Coccygeal nerve- 1 nerve around
     coccyx
I. Spinal Nerves
F. 13 Spinal Nerve
   Branches To Know:
   1. Phrenic- diaphragm
   2. Axillary- circumflex
      shoulder
   3. Ulnar- arm and hand
      muscles; senses
   4. Median-
       “
   5. Radial-
       “
   6. Pudendal- perineal
      muscles in genitalia,
      senses
I. Spinal Nerves
F. 13 Spinal Nerve Branches To Know:
   7. Femoral- leg muscles
   8. Lateral Femoral Cutaneous- senses of thigh
   9. Saphenous- towards patella, senses
   10. Sciatic- largest nerve- ¾ in diameter, back thigh, muscles
   11. Tibial- off sciatic, lower leg, senses
   12. Common Peroneal- leg and foot muscles, senses
   13. Medial Cutaneous- lower leg, senses
II. Cranial Nerves
Consist of bundles of axons
Named based on primary function or structure that
  they serve
A. Three Kinds- sensory, motor, mixed
II. Cranial Nerves
                                     I. Olfactory
B. Cranial Nerves to Know:
  I. Olfactory- smell- S             II. Optic

  II. Optic- vision- S               III. Oculomotor
  III. Oculomotor- eye mover- M
                                     IV. Trochlear
  IV. Trochlear- eye mover- M
  V. Trigeminal- largest, chewing,   V. Trigeminal
     sensation-B                     VI. Abducens
  VI. Abducens- eye mover-M          VII. Facial
  VII. Facial- taste, tears- B
 II. Cranial Nerves
B. Cranial Nerves to Know:       VII. Vestibulocochlear

  VIII-Vestibulocochlear-
    hearing, balance- S           IX. Glossopharyngeal

  IX- Glossopharyngeal- taste,
    moves tongue- B
                                     X. Vagus
  X- Vagus- thoracic and
    abdominal cavities- B           XI. Accessory

  XI- Accessory- helps vagus
    nerve, larynx, pharynx,
    upper shoulder muscles- M
                                 XII. Hypoglossal
  XII- Hypoglossal-moves
    tongue- M
II. Cranial Nerves
WAYS TO HELP YOU REMEMBER THE NERVES-

On Old Olympus’ Towering Tops A Friendly Viking
 Grew Vines And Hops

On Occasion Our Trusty Truck Acts Funny- Very
 Good Vehicle Any How
II. Cranial Nerves
   WAYS TO HELP YOU REMEMBER Sensory,
    Motor, or Both-

   Some Say Marry Money But My Brother Says
    (its) Bad Business (to) Marry Money
III. Two Divisions of the PNS
A. Somatic Nervous System (SNS)
  1. Regulates voluntary effectors to carry signal to the
    viscera
  2. Regulates skeletal muscles
  3. Somatic Motor Pathway-
    brain or SC  single motor neuron with myelin 
    synapse with Ach  skeletal muscle
III. Two Divisions of the PNS
B. Autonomic Nervous System (ANS)
  1. Regulates involuntary effectors to carry signals to
    viscera
  2. Regulate cardiac muscle, smooth muscle, and
    glandular epithelial tissue
  3. 2 Divisions
     A. Sympathetic Division- Flight or Fight
     B. Parasympathetic Division- Rest and Repair
QUIZ Section 14 vocab
1. Halare: to breathe
2. Phil-: love
3. Muc-: mucus
4. Pulmo: lung
5. Penia-: deficiency
6. Alvus: belly
7. Man- hand
8. Nasus: nose
9. Megalo-: large
10. Dent: tooth
11. Pleura: side
12. Malaco: softening