ch. 14 nervous system spinal nerves
lateral cord, posterior cord, medial cord
Label the cords of the brachial plexus
Posterior gray horn, posterior gray commissure, lateral gray horn, anterior gray horn, anterior gray commissure, somatic, visceral, viscera, somatic, sensory nuclei, motor nuclei
Label the features of gray matter
Pia matter, arachnoid matter, dura matter
Label the features of spinal meninges
cervical enlargement, lumbosacral enlargement, conus medularis, cuada equina
Label the features of the spinal cord
dorsal root, dorsal root ganglion, spinal nerve, ventral root, white matter, gray matter
Label the features of the spinal cord (cross section)
Epineurium, perineurium, endoneurium
Label the features of the spinal nerve
Cervical plexus, brachial plexus, lumbar plexus, sacral plexus
Label the nerve plexuses
Musculocutaneous nerve, median nerve, ulnar nerve, radial nerve
Label the nerves of the brachial plexus
Musculocutaneous nerve, median nerve, ulnar nerve, radial nerve, ulnar nerve, median nerve, anterior interosseous nerve, palmar digital nerves
Label the nerves of the brachial plexus
axillary nerve, radial nerve, posterior antebrachial cutaneous nerve, dorsal digital nerves
Label the nerves of the brachial plexus
Lesser occipital nerve, surpraclavicular nerve, great auricular nerve, transverse cervical nerve
Label the nerves of the cervical plexus
Phrenic nerve
Label the nerves of the cervical plexus
iliohypogastric nerve, ilioinguinal nerve, genitofemoral nerve, lateral cutaneous nerve of thich, femoral nerve
Label the nerves of the lumbosacral plexus
iliohypogastric nerve, ilioinguinal nerve, genitofemoral nerve, lateral femoral cutaneous nerve, femoral nerve, obturator nerve
Label the nerves of the lumbosacral plexus
saphenous nerve
Label the nerves of the lumbosacral plexus
tibial nerve, superior gluteal nerve, inferior gluteal nerve, sciatic nerve, common fibular nerve
Label the nerves of the lumbosacral plexus (posterior)
pudenal nerve
Label the nerves of the sacral plexus
superior gluteal nerve, inferior gluteal nerve, sciatic nerve, posterior femoral cutaneous nerve, pudenal nerve
Label the nerves of the sacral plexus
blood vessel, epineurium, perineurium, endoneurium, schwann cell, fascicle, myelinated axon
Label the peripheral nerve
Superior trunk, middle trunk, inferior trunk
Label the trunks of the brachial plexus
from interoceptors of back, from exteroceptors and proprioceptors of back, from exteroceptors and proprioceptors of body wall and limbs, from interoceptors of body wall and limbs, from interoceptors of visceral organs
Label where the sensory info is coming from
Endoneurium of spinal nerve:
Layer surrounding a single axon
How many pairs of coccygeal nerves?
1
How many pairs of thoracic spinal nerves?
12
Why do we have an 8th pair of cervical nerves if we only have 7 cervical vertebrae?
1st nerve starts at the top of the atlas and all the nerves are in between the vertebrae so the 8th pair is in between C7 and T1.
How many pairs of spinal nerves are there?
31
How long is the spinal cord and what does it pass through?
45 cm, foramen magnum
How many pairs of lumbar spinal nerves?
5
How many pairs of sacral spinal nerves?
5
How many pairs of cervical spinal nerves?
8
Reflex arc:
Begins at a sensory receptor and ends at a peripheral receptor
To avoid damaging the spinal cord during a spinal tap, the needle should be inserted _____.
Below L1-L2
What vertebrae does the cervical plexus extend from?
C1 - C5
What vertebrae does the brachial plexus extend from?
C5 - T1
postganglionic fibers to smooth muscles/ glands of back, to skeletal muscles of back, to skeletal muscles of limbs, post ganglionic fibers to smooth muscle/glands of limbs, postganglionic fibers to smooth muscles, glands, visceral organs of thoracic cavity, preganglionic fibers to sympathetic ganglia innervating abdominopelvic viscera
Name the areas that are being traveled to by structures in the motor command
Dorsal ramus, ventral ramus, gray ramus, rami communicantes, white ramus, sympathetic nerve, dorsal root ganglion, dorsal root, visceral motor, somatic motor, ventral root, spinal nerve, sympathetic ganglion
Name the structures of the motor commands
What kind of nerve is dorsal root?
sensory
What two types of nuclei are there?
sensory nuclei and motor nuclei
What do the columns of white matter convey? (describe)
sensory tracts - ascending tracts motor tracts - descending tracts
What does gray matter consist of?
somas (cell bodies)
What are the two types of response reflexes?
somatic - control skeletal muscle contractions, include superficial and stretch reflexes visceral (autonomic) relfexes - controls actions of smooth and cardiac muscles and glands
Anterior gray horns of gray matter are made up of what nuclei?
somatic motor
Posterior gray horns of gray matter are made up of what nuclei?
somatic sensory and visceral
What are the two types of reflexes classified by processing site?
spinal reflexes - processing in the spinal cord cranial reflexes - processing in the brain
Pathway of stretch reflex (monosynaptic)
stimulus - stretching of muscle stimulates muscle spindles, activation of sensory neuron, information processing at motor neuron, activation of motor neuron, response - contraction of muscle
what does cerebrospinal fluid do and where is it located?
subarachnoid space - acts as a shock absorber and diffusion medium for dissolved gases, nutrients, chemical messengers, and waste products
What are the nerves of the sacral plexus?
superior and inferior gluteals, sciatic nerve, pudendal nerve, posterior femoral cutaneous nerve
What trunks does the brachial plexus consist of?
superior, middle, inferior
What does the ventral ramus do?
supplies ventrolateral body surface, body wall structures, and limbs
what are denticulate ligaments
supporting fibers extending laterally from the spinal cord surface, binding the spinal pia mater and arachnoid mater to dura mater to prevent side to side movement of spinal cord
WHat kind of nerves does the brachial plexus consist of?
terminal nerves
If the sciatic nerve were compressed, which area of the leg would NOT be affected?
the medial side of the thigh
What is the cauda equina?
the nerve travel down past the spine, looks like a horses maine
Motor nerves (efferent nerves)
transmit impulses away from the spinal cord
sensory nerves (afferent nerves):
transmit impulses toward the spinal cord
What does the ventral root of a spinal nerve contain?
visceral and somatic motor nerve axons
Lateral gray horns of gray matter are made up of what kind of nuclei
visceral motor
what is the epidural space?
what separates the dura matter from the inner walls of the vertebral canal
What is a fascicle
a bundle of axons
What divisions does the brachial plexus consist of?
anterior and posterior
Pathway of a withdrawel (flexor) reflex?
arrival of stimulus/ activation of receptor, activiation of sensory neuron, info processing in CNS, activation of a motor neuron, response by effector
where do ascending tracts and descending tracts relay information to and from?
ascending - from spinal cord to brain descending - from brain to spinal crod
What does gray commissure consist of?
axons crossing from one side to the other
What does the white matter consist of, how are nerves organized, where is it located?
axons, tracts columns, outside the gray matter
Why does the spinal cord get larger at the cervical englargement and lumbosacral enlargement
because of upper and lower limbs
The spinal cord extends from ____ to ______
brain, L1
All the axons within a particular tract...
carry either sensory or motor information, are of approximately the same diameter, carry information to approximately the same location
What are the four nerve plexuses and what two are sometimes combined?
cervical, brachial, lumbar, sacral - sometimes lumbosacral plexus
What regions do the spinal cord consist of?
cervical, thoracic, lumbar, sacral, coccygeal
What structure of the ear is responsible for hearing?
cochlea
What does white matter consist of?
columns of nerves (fascicles)
What does the sciatic nerve branch to form?
common fibular and tibial nerve
The spinal cord ends at what?
conus medullaris
What are spinal meninges continuous with?
cranial (cerebral) meninges
What branches does the cervical plexus consist of?
cutaneous and muscular branches
What merges to form a spinal nerve?
dorsal root and ventral root
If a mosquito lands upon Tyrone's arm, the electrical message conveying the detection of the mosquito would travel through which structure?
dorsal root ganglion
What three layers are the spinal meninges made of (explain what each layer is)
dura mater - tough, fibrous outermost layer arachnoid mater - middle layer pia matter - innermost layer
When a woman in labor recieves an epidural injection of anesthesia where does it go?
epidural space
What is excreted by the adrenal gland?
epinephrine and nonepinephrine
What does each peripheral spinal nerve consist of?
epineurium perineurium endoneurium
The cutaneous branch of the cervical plexus innervates what?
head, neck, shoulder region
What are the nerves of the lumbar plexus?
iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, nerves to iliopsoas, femoral nerve, obturator
Reflex:
immediate involuntary response
What direction do sensory impulses travel:
in the spinal nerve through the dorsal root to the spinal cord
What are the two types of development reflexes?
innate - genetically determined acquired - learned
What do the brain and spinal cord do?
integrate and process information
What do the spinal nerves emerge from?
intervertebral foramina
ventral root, dorsal root, pia matter, arachnoid matter, gray matter, spinal nerve, dorsal root ganglion, dura matter
label the spinal cord/spinal meninge
Perineurium of spinal nerve:
layer surrounding a fascicle
The middle nasal conchae is part of which bone?
maxilla
What cords does the brachial plexus consist of?
medial lateral posterior,
What are the two types of reflexes classified by complexity of circuit?
monosynaptic - one synapse polysynaptic - multiple synapses
What kind of nerve is ventral root?
motor
somas are organized into what?
nuclei
The muscular branch of the cervical plexus innervates what?
omohyoid, sternohyoid, geniohyoid, thyrohyoid, sternothyroid, scalenes, and diaphragm
Epineurium of spinal nerve:
outer layer that becomes continuous with dura matter
What does each of the the 31 segments of the spinal cord have (disregarding exception)
pair of dorsal root ganglia, pairs of dorsal roots and pairs of ventral roots
What forms the blood-nerve barrier?
perineurium
What nerve controls the diaphragm?
phrenic nerve of cervical plexus
Gray ramus is also _____ and white ramus is also ______
postganglionic, preganglionic
What do the spinal meninges do?
protect the cord from injury that would be caused by rubbing against a vertebral foramen, isolate the spinal cord from surrounding tissue, absorb shock transmitted up the body when walking, running, or other vigorous motions occur
spinal meninges are specialized membranes that provide what?
protection, physical stability, and shock absorption
What does the dorsal ramus do and where is it found?
provides sensory/motor innervation to the skin and muscles of the back - each spinal nerve
What is the oculomotor nerve responsible for?
pupil restriction
What are the white and gray ramus collectively called?
rami communicaters
DERMATOMES DONT FORGET***
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What are the four branches of the spinal nerves?
Whit ramus, gray ramus, dorsal primary ramus, ventral primary ramus
What are the two exceptions to the rule that each segment of the spinal cord is associated with a pair of dorsal roots?
The first cervical and first coccygeal nerves