peripheral & central nervous systems

ganglia definition

collection of neurons outside the CNS

spinal ganglia definition

where cell bodies of sensory neurons associated with spinal nerves are located

dorsal root ganglia definition

alternate name for spinal ganglia, which are part of the dorsal root of the spinal nerve

where cell bodies of sensory neurons associated with spinal nerves are located

in spinal ganglia

autonomic ganglion definition

the location of the cell body of the second neuron in a 2-neuron chain of autonomic nerves

where the spinal cord begins

at the foramen magnum

the spinal cord extends to the level of the disc between vertebrae ___ and ____

L1, L2

the spinal cord is a continuation of ___

the brainstem

the spinal cord is located in the ____ of the vertebral canal

upper 2/3

spinal segment definition

the length of the spinal cord to which one pair of spinal nerves is attached

up until ___, nerve roots emerge ____ (superior/inferior) to their respective vertebrae

C8, superior

T1 exits ___ (superior/inferior) to the T1 vertebrae

inferior

where C8 exits from the spinal cord

inferior to the C7 vertebrae

identify 1

cervical enlargement

identify 2

lumbar enlargement

identify 3

conus medullaris

identify 4

filum terminale

identify 5

coccygeal nerve

where nerves exit the vertebral column from

intervertebral foramina, between vertebrae

spinal nerves are vulnerable to injury by a ____ or pathological ____ as they exit the vertebral column

herniated intervertebral disk, narrowing of the intervertebral foramen

motor rootlets converge to form ___

ventral roots

what the ventral roots innervate

skeletal muscle in the neck, trunk, and limbs

ventral roots carry ____ (motor/sensory/mixed) information ____ (to/from) the spinal cord

motor

from

sensory rootlets converge to form ____

dorsal roots

dorsal roots carry ____ (motor/sensory/mixed) information ___ (to/from) the spinal cord

sensory

to

dorsal roots send information toward the cell body located in the ___, then through the dorsal root to the spinal cord

dorsal root ganglion

identify 1

posterior/dorsal gray horns

identify 2

posterior/dorsal rootlets

identify 3

anterior/ventral rootlets

identify 4

posterior/dorsal root

identify 5

anterior/ventral root

identify 6

spinal (sensory/dorsal) ganglion

identify 7

denticulate ligament

identify 8

posterior/dorsal ramus

identify 9

anterior/ventral ramus

identify 10

mixed spinal nerve

identify 11

anterior gray horns

spinal nerve is made by the combination of ____

a ventral root and a dorsal root

the spinal nerve is ___ (long/short)

short

the spinal nerve divides into a ___ and ____

posterior/dorsal ramus and an anterior/ventral ramus

the dorsal ramus innervates _____

the muscles and skin of the back

the ventral rami innervate ___

the muscles and skin of the other anterior + lateral aspects of the neck and trunk

T/F: the ventral rami are larger than the dorsal rami

true

the ventral form ___ to innervate the limbs

plexuses

T/F: the dorsal rami branch to form cervical, brachial, lumbar, and sacral plexuses

false

only ventral rami do

the ____ provides the bulk of innervation for the upper extremity

brachial plexus

the ____ provide the bulk of innervation for the lower extremity and pelvis

lumbar and sacral plexuses

sensory information is sent to the CNS via ____

dorsal roots

motor information is sent out from the CNS via ___

ventral roots

the dorsal root is connected to the ____ of the spinal cord

dorsal/posterior horn

the ventral root is connected to the ____ of the spinal cord

ventral/anterior horn

the ventral root joins the dorsal root distal to the ___ to form the spinal nerve

ganglion

muscles in the head are innervated by ____

cranial nerves

reflex pathway definition

where sensory and motor neurons are connected within the CNS

example of reflex pathway + describe

patellar reflex

tap on patellar ligament → detected by sensory neurons in femoral nerve → transmit info to spinal cord → motor neurons in femoral nerve respond → contract quads muscle

identify 1

posterior horn

identify 2

lateral horn

identify 3

anterior horn

identify 4

ventral root

identify 5

sympathetic chain ganglia

identify 6

rami communicantes

identify 7

skeletal muscles

identify 8

sensory endings

identify 9

ventral ramus

identify 10

dorsal ramus

identify 11

spinal nerve

identify 12

spinal ganglion

identify 13

dorsal root

T/F: only dorsal roots send information through spinal ganglion

true

vemtral spinal ganglion don’t exist

C6 key dermatome

thumb

C7 key dermatome

index and middle fingers

C8 key dermatome

ring and little fingers

C5-T2 key dermatome

upper limb

T4 key dermatome

nipple

T10 key dermatome

umbilicus

the 3 meninges, from outermost to innermost

dura mater, arachnoid mater, pia mater

dura mater extends to the ___ level

S2

arachnoid mater extends below to the ___ level

S2

at __, the pia mater continues as the filum terminale

L2

the filum terminale is an extension of the ___

pia mater

the filum terminale perforates the ___ and ___ at S2 and continues within the coccygeal ligament

arachnoid mater and dura mater

the spinal cords ends at the level of the disc between the ___ and ___ vertebrae

L1, L2

cauda equina definition

the descending roots of the lower spinal nerves, since the spinal cords end before their exit

location of spinal tap/lumbar puncture (space and level)

subarachoid space between L3-L4 or L4-L5, after termination of the spinal cord

landmark used for spinal taps

an imaginary line connecting the highest points on the iliac crests, corresponding to L4 spine

polio is an example of a ___ lesion

purely motor

polio occurs especially in the ___ part of the spinal cord

lumbosacral

herpes zoster lays dormant in the ___

dorsal root ganglia

herpes zoster re-emerges in ___

peripheral sensory nerves

herpes zoster is an example of ___ lesion

purely sensory

herniated discs most often herniate in the ___ direction

posterolateral

a herniated disc is an example of a ___ lesion

mixed motor and sensory lesion

the preganglionic neuron is located ____ and the postganglionic neuron is located ___

in the CNS

in autonomic ganglia outside the CNS

T/F: only the autonomic system and pre- and post-ganglionic neurons

true

the cell bodies of sympathetic preganglionic neurons are located _____ (level and location)

the T1-L2 spinal cord segments, in the lateral horn of the gray matter

axons of sympathetic preganglionic neurons leave the spinal cord through ___ and enter the ____

ventral roots

sympathetic trunk

sympathetic innervation of muscles and glands in the head come from postganglionic neurons in the _____

superior cervical sympathetic ganglion

sympathetic postganglionic neurons innervating the head have axons that follow the ___ to reach the head

internal and external carotid arteries

parasympathetic preganglionic neurons are located in ____ (level and location)

the brain stem and S2-S4 spinal cord segments

parasympathetic preganglionic neurons travel in ______ and ____ nerves

cranial nerves III, VII, IX, X

spinal nerves S2-S4