Introduction to the Nervous System

Question 1

Ganglion

Answer 1

Collection of nerve cell bodies (in the PNS)

Question 2

Tract

Answer 2

Bundle of axons in the CNS

Question 3

Nerve

Answer 3

Bundle of axons in the PNS

Question 4

Bundles of axons can be all from the same modality but are normally mixed. Modalities:

Answer 4

Somatic sensory, somatic motor, special sensory, visceral afferent, sympathetic, parasympathetic

Question 5

Spinal nerves and branches are mixed -

Answer 5

Somatic motor, somatic sensory, sympathetic

Question 6

How many cranial nerves are mixed?

Answer 6

5

Question 7

Motor

Answer 7

Efferent

Question 8

Sensory

Answer 8

Afferent

Question 9

Motor (efferent):

Answer 9

Action potential towards the body wall, body cavity or organ

Question 10

Sensory (afferent):

Answer 10

Action potential towards the brain

Question 11

Spinal cord connects to…

Answer 11

The brain

Question 12

Spinal cord passes through…

Answer 12

foramen magnum

Question 13

Spinal cord protected by…

Answer 13

Vertebral column

Question 14

4 segments of spinal cord:

Answer 14

Cervical (C1-C7)
Thoracic (T1-T12)
Lumbar (L1-L5)
Sacral (S1-S5)/coccygeal (Co)

Question 15

2 enlargements of spinal cord

Answer 15

Cervical and lumbosacral
For innovation and control of limbs

Question 16

Where does the spinal cord end?

Answer 16

L1/L2 IV disc level — conus medullaris

Question 17

Lumbar and Sarah spinal nerve roots descend in…

Answer 17

The vertebral canal and form the cauda equina

Question 18

Peripheral nervous system

Answer 18

All other nerve tissues not within the CNS

Question 19

Peripheral nerves

Answer 19

Bundles of axons wrapped in connective tissue, which are travelling to/from the same structure
Bundles of nerves can leave as ‘branches’

Question 20

Spinal nerves

Answer 20

Connect with spinal cord

Question 21

Cranial nerves

Answer 21

Connect with brain

Question 22

Autonomic nerves

Answer 22

Innervate organs, smooth muscle, glands
Visceral afferents, sympathetic nerves, parasympathetic nerves

Question 23

How does the spinal cord connect with spinal nerves?

Answer 23

Bilaterally - 31 pairs

Question 24

What is a spinal nerve named after?

Answer 24

The vertebrae above it, except for the cervical region where they are named according to the vertebrae below (C8 exits between C7 and T1 vertebrae)

Question 25

What do the spinal nerves supply?

Answer 25

The soma (body wall)

Question 26

Spinal nerves are located...

Answer 26

Only within the intervertebral (IV) foramina

Question 27

From the IV foramina, spinal nerves connect with…

Answer 27

Structures of the soma via rami The spinal cord via roots and rootlets

Question 28

Posterior rami

Answer 28

Supply small posterior strip of the soma (back)

Question 29

Anterior rami

Answer 29

Supply the remainder of the posterior part, the lateral and anterior parts of the strips of the soma Supply all of the limbs via plexus - networks of intertwined anterior rami

Question 30

Cervical plexus

Answer 30

C1-C4 anterior rami, supplies the posterior scalp, neck wall, diaphragm

Question 31

Brachial plexus

Answer 31

C5-T1 anterior rami; supplies there upper limb

Question 32

Lumbar plexus

Answer 32

L1-L4 anterior rami, supplies the lower limb

Question 33

Sacral plexus

Answer 33

L5-S4 avertir rami, supplies the lower limb, gluteal region and perineum

Question 34

Dermatomes

Answer 34

Area of skin supplied by both the anterior and posterior rami of a spinal nerve Exception - limbs (no posterior rami)

Question 35

T4 dermatome

Answer 35

nipple

Question 36

T10 dermatome

Answer 36

umbilicus (belly button)

Question 37

what are dermatome maps used for?

Answer 37

To illustrate dermatomes

Question 38

CN I

Answer 38

olfactory nerve sensory (special)

Question 39

CN II

Answer 39

optic nerve sensory (special)

Question 40

CN III

Answer 40

oculomotor nerve motor

Question 41

CN IV

Answer 41

trochlear nerve motor

Question 42

CN V

Answer 42

trigeminal nerve both

Question 43

CN VI

Answer 43

abducent nerve motor

Question 44

`CN VII

Answer 44

facial nerve both

Question 45

CN VIII

Answer 45

vestibulocochlear nerve sensory (special)

Question 46

CN IX

Answer 46

glossopharyngeal nerve both

Question 47

CN X

Answer 47

vagus nerve both

Question 48

CN XI

Answer 48

spinal accessory nerve motor

Question 49

CN XII

Answer 49

hypoglossal nerve motor

Question 50

cranial forminae for CN I

Answer 50

cribriform plate of the ethmoid bone

Question 51

cranial forminae for CN II

Answer 51

optic canal

Question 52

cranial forminae for CN III, IV, V1 & VI

Answer 52

superior orbital fissure

Question 53

cranial forminae for CN V2

Answer 53

foramen rotundum

Question 54

cranial forminae for CN V3

Answer 54

foramen ovale

Question 55

cranial forminae for CN VII & VIII

Answer 55

internal acoustic meatus

Question 56

cranial forminae for CN IX, X & XI

Answer 56

jugular formen

Question 57

cranial forminae for CN XII

Answer 57

hypoglossal canal

Question 58

soma

Answer 58

body wall (external environment)

Question 59

soma includes...

Answer 59

head and neck walls, chest walls, back, diaphragm, abdominal wall, pelvic wall, limbs

Question 60

soma structures...

Answer 60

skin, fascia, skeletal muscle, skeleton, internal lining of body cavities

Question 61

mechanoreceptors

Answer 61

sense coarse and fine touch, vibration, propiroception

Question 62

thermoreceptors

Answer 62

sense temperature

Question 63

nociceptors

Answer 63

sense pain (sharp, stabbing, well localised)

Question 64

somatic sensation pathway to the brain

Answer 64

sensory receptors stimulated → anterior ramus → plexus (e.g. lumbar) → dorsal root ganglion → dorsal roots → dorsal rootlets → posterior horn → cross over midline and action potentials ascend towards brain

Question 65

motor innervation pathway to skeletal muscle

Answer 65

somatic motor axons cross over in brainstem then descend to anterior horn → anterior rootlets → anterior roots → spinal nerves → plexus → synapse onto skeletal muscle which contracts

Question 66

spinal reflexes

Answer 66

rapid - misses out pathways to the brain involuntary - protective function

Question 67

visceral motor system