Lecture 19: Spinal Cord and Somatic NS

Question 1

2 functional divisions of PNS

Answer 1

-visceral
-somatic

Question 2

where do spinal nerves pass through

Answer 2

intervertebral foramina

Question 3

anatomical divisions of nervous system

Answer 3

-PNS
-CNS

Question 4

somatic NS innervates what structures (general)

Answer 4

-body wall (parietal structures)

Question 5

somatic NS: function

Answer 5

voluntary motor control over skeletal muscle

Question 6

what is the spinal nerve complex

Answer 6

somatic nervous system + part of ANS

Question 7

gray matter contains what part of neuron

Answer 7

-cell bodies

Question 8

white matter contains what part of neurons

Answer 8

axons

Question 9

2 main structures within gray matter

Answer 9

-dorsal horn
-ventral horn

Question 10

do spinal nerve levels and vertebral levels match

Answer 10

no

Question 11

where does spinal cord end

Answer 11

-before vertebrae
-at conus medularis

Question 12

where is spinal cord continuous with brain stem

Answer 12

foramen magnum

Question 13

why is there differential growth between spinal cord and vertebral column

Answer 13

vertebral column grows faster

Question 14

sensory = (afferent or efferent)

Answer 14

afferent

Question 15

afferent =

Answer 15

towards CNS

Question 16

motor = (afferent or efferent)

Answer 16

efferent

Question 17

efferent =

Answer 17

away from CNS

Question 18

2 divisions of visceral PNS

Answer 18

-ANS
-sensory

Question 19

2 divisions of ANS

Answer 19

-sympathetic
-parasympathetic

Question 20

how many cervical nerves and vertebrae are there

Answer 20

-7 vertebrae
-8 spinal nerves

Question 21

why are there 8 cervical spinal nerves but only 7 vertebrae

Answer 21

spinal nerves for cervical vertebrae exit cranially to vertebrae from C1-C7

Question 22

cervical vs thoracic/lumbar/sacral spinal nerves (exit location)

Answer 22

-cervical nerves pass cranially over vertebrae
-thoracic nerves pass caudally over vertebrae

Question 23

where are somatic motor cell bodies found

Answer 23

ventral horn

Question 24

where do somatic motor axons leave

Answer 24

ventral root

Question 25

where are sensory cell bodies found

Answer 25

dorsal root ganglion

Question 26

where do sensory axons travel

Answer 26

dorsal root

Question 27

type of neurons found in dorsal root ganglion (hint: sensory)

Answer 27

pseudounipolar

Question 28

what is the mixed spinal nerve (what kind of information is found here)

Answer 28

-where dorsal and ventral roots are joined/fused -mixed motor and sensory

Question 29

dorsal rami go to __________ musculature

Answer 29

epaxial

Question 30

ventral rami go to __________ musculature

Answer 30

hypaxial

Question 31

CNS gray matter contains (3)

Answer 31

-cell bodies of neurons (glial cells) -dendrites -neuropil

Question 32

what are CNS gray matter neurons organized into

Answer 32

nuclei

Question 33

is there connective tissue in CNS gray matter

Answer 33

no

Question 34

CNS white matter contains (2)

Answer 34

-axons, myelinated -glial cells

Question 35

CNS white matter axons are organized into ________

Answer 35

tracts

Question 36

cauda equina

Answer 36

extension of dorsal and ventral roots to the same numbered vertebral level

Question 37

each spinal nerve complex is responsible for what

Answer 37

-1 dermatome/body segment

Question 38

epaxial muscles

Answer 38

-internal muscles of back -longissimus, iliocostalis, transversospinalis

Question 39

somatic motor innervation to latissimus dorsi (or any other hypaxial muscle)

Answer 39

ventral horn --> ventral root --> mixed spinal nerve --> ventral ramus

Question 40

somatic sensory innervation from skin

Answer 40

ventral ramus --> mixed spinal nerve --> dorsal root ganglion (where sensory CELL BODIES are found) --> dorsal root --> dorsal horn

Question 41

meninges: definition

Answer 41

-coverings of spinal cord

Question 42

what kind of tissue are meninges made of

Answer 42

connective tissue

Question 43

3 meninges in spinal cord

Answer 43

-dura mater -arachnoid mater -pia mater

Question 44

what is the outermost/superficial layer of meninges

Answer 44

dura mater

Question 45

dura mater: features

Answer 45

-tough and thick -continuous with dura of brain -surrounded by extradural fat in epidural space

Question 46

where does dura mater extend to

Answer 46

laterally onto proximal spinal nerves

Question 47

where/how is dura mater anchored

Answer 47

-to caudal vertebrae via filum terminale

Question 48

what is the filum terminale

Answer 48

-portion of cauda equina -fibrous extension of cord down to coccyx

Question 49

2 parts of filum terminale

Answer 49

-internus -externus

Question 50

the internus is made out of which meninge

Answer 50

pia mater

Question 51

the externus is made out of which meninges

Answer 51

all 3

Question 52

location of arachnoid mater

Answer 52

deep and adherent to dura mater

Question 53

which meninge is filled with CSF

Answer 53

arachnoid

Question 54

the arachnoid mater encloses what space

Answer 54

subarachnoid space

Question 55

arachnoid mater: features

Answer 55

-thin and delicate -spiderlike

Question 56

arachnoid mater is continuous with what structure

Answer 56

subarachnoid space around brain

Question 57

what is the innermost meningeal layer

Answer 57

pia mater

Question 58

pia mater location

Answer 58

attached to spinal cord

Question 59

what does pia mater create (2)

Answer 59

-denticulate ligaments -filum terminal internus

Question 60

what are denticulate ligaments

Answer 60

lateral expansions of pia between rootlets to anchor spinal cord to dura mater