GA1 - Peripheral Nervous System Flashcards
Neuron/ nerve cell
A specialized cell capable of transmitting electrical impulses
Primary functional unit of the NS
3 parts of a neuron
dendrites (branches), cell body/soma, and axon
soma contains
nucleus and most of cytoplasm
2 types of axons
myelinated or unmyelinated
myelinated
enshealthed by Schwann Cells
3 types of neurons according to function
sensory, motor, and interneuron
3 types of neurons according to structure
unipolor/pseudounipolar, bipolar, or multipolar
sensory neurons
afferent: receiving electrical impulse
periphery to cell body
motor neurons
efferent: away from cell body
interneuron
go between: can serve as a connection between sensory and motor neurons
unipolar neurons
1 cytoplasmic process
bipolar neuron
1 dendrite and 1 axon
seen in sensory organs (eye, retina and hearing)
multipolar neuron
1 axon and multiple dendrites
lower motor neurons in the ventral horn of the spinal cord
CNS contains…
brain and spinal cord
PNS (functional) 2 types
Somatic NS and Visceral NS
Somatic NS 2 types
Somatic sensory and somatic motor
somatic refers to
bone, cartilage, tendon, ligaments, muscles, skin
makes up the body wall –> outer shell/skin
somatic sensory
receiving info from somatic structures
somatic motor
toward skeletal muscles only
visceral NS contains
visceral sensory and visceral motor (ANS)
visceral motor also called
Autonomic NS
visceral pertains to
heart, lungs, esophagus, and internal organs
visceral motor/ANS sends impulses to
smooth and cardiac muscles
2 types of ganglia (ganglion)
spinal and autonomic
ganglion is a
collection of nerve cell bodies outside of the CNS
ganglion are
encapsulated
spinal ganglia are located in the ______ and have what kind of neurons?
dorsal root ganglia/ primary sensory neurons
2 types of autonomic ganglia that are located where?
sympathetic and parasympathetic. smooth and cardiac muscle
cranial nerves arise from…
brain stem
how many pairs of cranial nerves?
12 pairs
C1 to C7 exits the spinal column right _____ the corresponding vertebrae
above
cervial nerve 8 exits between
C7 and T1
below the cervicals nerves exit ____ the corresponding vertebra
below
white matter of the spinal cord contain
myelinated axons
grey matter is in the shape of
an H or a butterfly
grey matter contains
cell bodies and the nucleus
dorsal horn has
sensory fibers and interneurons
vental horn has
lower motor neurons
dorsal root ganglia has ___ and is ____
primary sensory neuron and pseudounipolar
ventral horn innervates
skeletal muscles
ventral anterior rootlets contain
motor fibers
T1-L2 have an extra horn called the
lateral horn
grey matter has 2 horns
vental and dorsal
preganglionic sympathetic neurons innervate
smooth and cardiac muscles
dorsal ramus goes to
skin and deep back muscles
dorsal rootlet =
SENSORY
ventral roolet =
MOTOR
ROOT from
Rootlet
RAMUS from
DIRECTLY FROM NERVE
Ramus contains
both sensory and motor fibers
Root contains
EITHER sensory or motor
2 types of somatic fibers
general somatic afferent (sensory) and general somatic efferent (motor)
General somatic afferent (sensory)
GSA fibers. ex. pain from ankle sprain
General somatic efferent (motor)
GSE fibers. to skeletal muscles.
two types of visceral fibers
general visceral afferent (sensory) and general visceral efferent (motor)
general visceral afferent (sensory)
GVA. pain from heart. urge to urinate
general visceral efferent (motor)
GVE. contraction of urinary bladder. smooth and cardiac muscles. motility of food. GLANDULAR secretion
dermatome
dermis. nerve will migrate and carries sensory nerve fiber with it
dermatome ex - diaphragm
nerve originated from cervical myotome. nerve fiber from C3, C4, or C5
no C1 dermatome =
no sensation to the skin
C2 dermatome
back of the head; the highest dermatome of the body
C4 dermatome
top part of the shoulder
C6 dermatome
thumb
C7 dermatome
middle finger
C8 dermatome
little finger
T4 dermatome
level of the nipples
T10 dermatome
level of the umbilicus
T12/L1 dermatome
the skin along the inguinal crease
L4 dermatome
big toe
S1 dermatome
little toe and sole of the foot
S4/S5/Co 1 dermatome
the skin around the anus
dorsal does not form
a plexus
somatic nerve plexus is
a complex interwoven network of nerves formed by vental rami of adjacent spinal nerves
cervical plexus
C1-C4
brachial plexus
C5-T1
brachial plexus provides ____ and ____ innervation to
motor and sensory innervation to the upper extremities
lumbar plexus
L1-L4
Sacral plexus
L4-S4
cervical plexus goes to
the muscles and the skin
lumbar plexus provides innervation to
sensory to the thigh region of the lower extremities, genetalia, and motor and sensory to abdominal region
sacral plexus innervates
muscles of the gluteal region
the largest nerve in the body
Sacroiliac Joint
SIJ provides nerve supply to
the rest of the lower extremity that the lumbar region doesnt innervate
12 cranial nerves
olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, and hypoglossal
olfactory cranial nerve
smell
optic cranial nerve
sight
oculomotor cranial nerve
movement of the eye
trochlear cranial nerve
movement of the eye
trigeminal cranial nerve
muscles of mastication and sensation to the face
abducens cranial nerve
abduction of eye ball
facial cranial nerve
provide facial expression
vesibulocochlear cranial nerve
equilibrium; hearing and balance
glossopharyngeal cranial nerve
taste
vagus cranial nerve
taste and larynx
accessory cranial nerve
SCM and trapezius
hypoglossal cranial nerve
tongue, motor innervation to muscle of the tongue
mnemonic for cranial nerves
oh oh oh to touch and feel a virgin girls vagina, ah heaven
7 fiberss to cranial nerves
GSA, GSE, GVA, GVE, SSA, SVA, SVE
special fibers only found in
cranial nerves
3 types of special fibers
special somatic afferent, special visceral afferent, special visceral efferent
special somatic afferent (SSA) which cranial nerves?
2 and 8
special somatic afferent - somatic goes with which senses
vision and hearing
special visceral afferent (SVA) which cranial nerves
1, 7, 9, 10
special visceral efferent (SVE) which nerves
5, 7, 9, 10
special visceral efferent (SVE)
brachial motor, supply skeletal muscles of mastication, facial expression, larynx and pharynx
special visceral efferent (SVE) derived from
pharyngeal apparatus, not derived from myotome
referred pain
occurs when sensory info comes to the spinal cord, but is interpreted by the CNS as coming from another location innervated by the same spinal cord level
2 types of referred pain
viscero-somatic and somato-somatic
viscero-somatic referred pain
originated from visceral organ referring pain to a somatic structure. some visceral organs have pain through musculoskeleton
somato-somatic referred pain
somatic structure referring pain to another somatic structure
reflex arc
a signal conduction route to and from the CNS, with the electrical signal beginning in receptors and ending in effectors. they are automatic responses. sensory direct signals motor
two types of reflex arcs
three neuron arc and two neuron arc
three neuron arc
most common, consists of an afferent neurons, interneurons and efferent neurons. 2 synapses/polysynapses
interneuron
in spinal cord (grey matter) connects dorsal and ventral horn. is the mediator and cross over to maintain posture.
two neuron arc
simplest form. consists of afferent and efferent neurons. monosynaptic (1 synapse)
Motor Division (ANS) of the Visceral NS consists of
smooth and cardiac muscles and glandualr tissue (sweat and salivary)
ANS consists of two subdivisions
parasympathetic and sympathetic
cell bodies of preganglionic parasympathetic neurons found in
craniosacral - brainstem, S2-S4
2 types of Parasympathetic ganglia
cranial and intramural
location of postganglionic neurons in
cranial and intramural ganglia
preganglionic and postganlionic neurons will synapse at
ganglia
cranial and intramural ganglia found
near or within the target organ
cranial ganglia
parasympathetic, in the cranium, 4 pairs
4 pairs of cranial ganglia
ciliary, otic, pferygopalatine, submandibular
intramural ganglia
parasympathetic, found within the wall of the target organ, thoracic, abdominopelvic
function of parasympethic NS
energy conserving. slow down hear, predominant in rest or day to day activity. rest and digest. feed, breed or be.
preganglionic fiber of parasympathetic is
LONG
postganglionic fiber of parasympathetic is
SHORT
preganglionic neuron is
presynaptic
postganglionic neuron is
postsynaptic
preganglionic sympathetic neuron originate in the
lateral horn of grey matter of spinal cord of thoracolumbar T1-L2
Two sympathetic ganglia
paravertebral and prevertebral
paravertebral sympathetic ganglia
along side, either side of vertebral column, near the spinal cord, infront of the abdominal aorta, more near the midline
preganglionic neuron in the sympathetic NS of the paravertebral ganglia are
SHORT
postganglionic neuron in the sympathetic NS of the paravertebral ganglia are
LONG
preganglionic neuron in the sympathetic NS of the prevertebral ganglia are
medium in length
postganglionic neuron in the sympathetic NS of the prevertebral ganglia are
medium in length
function of the sympathetic NS
energy expending. fight, flight, or fright.
white rami communicantis
myelinated preganglionic sympathetic
gray rami communicantis
unmyelinated postganglionic sympathetic
