Nervous System

Question 1

Central Nervous System

Answer 1

brain and spinal cord

Question 2

Peripheral Nervous System

Answer 2

spinal nerves and cranial nerves

Question 3

Autonomic Nervous System

Answer 3

composed of PNS and CNS

Question 4

Meninges

Answer 4

• surround brain and spinal cord
  1. Pia: soft mother, delicate tissue, thin, stays close to brain tissue
  2. Arachnoid: spider web like, not crevices but still surround brain, where CSF is located
  3. Dura: continuous with epineurium, hard, surrounds brain and spinal cord and follow nerves that branch off SC

Question 5

PNS

Answer 5

• meninges: only dura is present within PNS
• spinal nerves: ventral and dorsal root, APR, PPR (anterior/ posterior primary rami)
• neuromuscular junction (structure of peripheral nerve)
• dermatome vs mytome
• peripheral nerves and plexus’s
• neural tension

Question 6

PNS General Pathway

Answer 6

• Sensory: afferent, posterior
• Motor: efferent, anterior
• IMPORTANT: review Lecture 1 slides 51-54

Question 7

Nerve Structure

Answer 7

• epineurium: continuation of dura mater
• perineurium: sheath of connective tissue surrounding a bundle (fascicle) of nerve fibers within a nerve
• fascicle
• myelin sheathe (protects axon)

Question 8

Neuromuscular Junction

Answer 8

• cell body
• axon: efferent
• dendrites: afferent information

Question 9

Dermatomes

Answer 9

• area of skin that receives nerve function from the sensory portion of a single nerve root
• ex: C7 dermatome provides sensation to 3rd digit and middle aspect of hand
• see Lecture 1, slides 58-60

Question 10

Myotomes

Answer 10

• group of muscles that receive nerve input from primarily one motor portion of nerve root
• ex: C7 myotome provides primary motor input for elbow extension, also aids in wrist flex/ext, shoulder add

Question 11

Plexus

Answer 11

• APR’s of nerve roots in a specific region join and separate other nerves by way of plexus’s: brachial, lumbar, cervical, sacral, coccygeal
• nerves continue on as peripheral nerves with specific names

Question 12

Peripheral Nerve

Answer 12

• contains 2-3+ spinal nerve roots
• in general, if muscle is innervated by 3 nerve roots, the middle nerve root is primary innervation, ex: triceps innervated by radial nerve c6,c7,c8
• most muscles are innervated by a single peripheral nerve
• most peripheral nerves have cutaneous distribution, which differs from dermatome

Question 13

Damage to C5 vs. Musculocutaneous Nerve

Answer 13

C5
- dermatome: along lateral aspect of proximal arm
- myotome: primarily elbow flexion, but also shoulder abd, and glenohumeral jnt lateral toration
-signs/symptoms: weak elbow flexion, altered sensation along lateral aspect of proximal arm
Musculataneous Nerve:
- composed of C5, C6, C7
-innervates biceps brachii, brachilais, coracobrachialis
- signs and symptoms: very weak elbow flexion, decreased sensation along lateral aspect of forearm via lateral cutaneous nerve of forearm

Question 14

Vascular System

Answer 14

See Lecture 1, Slides 68-69

Question 15

Lymphatic System

Answer 15

• lymphocytes: circulating cells of immune system
• lymphoid organs: thymus, red bone marrow, spleen, tonsils, appendix
• lymph nodes: small masses of lymph tissue through which lymph is filtered
• lymph vessels; thin wall vessels that make up body, wide network to drain lymph near capillaries
• common way to spread cancer (mostly carcinomas)