Spinal Cord and Spinal Nerves

juliaterese's version from 2015-04-15 23:12

Section 1

Question Answer
contains neural circuits that control some of the quickest reactions to environmental changesspinal cord
site of integration for neuronal stimulationspinal cord
what is the spinal cord the highway of?upward and downward fibers, sensory to brain and motor from brain
what spinal cord is continuous with brain
protective structures of the spinal cordvertebral column, spinal meninges
CT coverings that encircle the brain and spinal cordspinal meninges
most superficial layer of spinal meningesdura mater
type of connective tissue dura mater isdense irregular
intermediate layer of spinal meninges arachnoid mater
type of connective tissue arachnoid mater isweb of collagen and some elastic fibers
deepest layer of spinal meningespia mater
layer of spinal meninges that adheres to spinal cordpia mater
space between dura mater and wall of the spinal cordepidural space
space between dura mater and arachnoid subdural space
what subdural space is filled with interstitial fluid
shock absorbing cushioning fluid that suspends nervous tissue in a weightless environmentCSF

Section 2

Question Answer
length of adult spinal cord42-45 cm
where spinal cord endsL2
diameter of spinal cord in mid thoracic region2 cm
when the spinal cord is fully formed 5 years old
where cervical enlargement isC1-C4 to T1
where lumbar enlargement endsT9-T12
tapered part of spinal cord inferior to lumbar enlargementconus medullaris
a tail-like array of roots of spinal nerves at the inferior end of the spinal cordcauda equina
non-nervous extension of pia mater that leads to coccyxfilum terminale

Section 3

Question Answer
myelinated neurons that cover gray matterwhite matter
wide groove in the white matteranterior median fissure
narrower than anterior median fissure, in white matter on dorsal sideposterior median sulcus
narrow strip of gray matter connecting the two lateral gray masses within the spinal cordgray commissure
a microscopic tube in the gray commisure that contains blood and lymphatic vessels and nervescentral canal
where in compact bone is the central canalthe center of an osteon
what central canal containsCSF
what white matter is subdivided intocolumns (anterior, posterior, lateral)
what each column containsascending and descending tracts
bundles of nerve axons in CNStracts
ascending tractssensory, conduct nerve impulses from spinal cord toward brain
descending tractsmotor, carry nerve impulses away from the brain down the spinal cord

Section 4

Question Answer
anterior to the gray commissure and connects the white matter of the right and left sides of the spinal cordanterior (ventral) white commissure
what gray matter is subdivided inhorns
what is contained in anterior gray hornssomatic motor nuclei
clusters of cell bodies of somatic motor neurons that provide nerve impulses for contraction of skeletal musclessomatic motor nuclei
what is contained by the posterior (dorsal) gray hornscell bodies and axons of interneurons, axons of incoming sensory neurons
what is contained by lateral gray hornscell bodies of autonomic motor nuclei
what autonomic motor nuclei regulateactivity of smooth muscle, cardiac muscle, glands
where lateral gray horns are only present in the spinal cordthoracic, upper lumbar, sacral segments

Section 5

Question Answer
result of injury to the spinal cord above T4respiratory failure, quadriplegic
result of injury further down the spinal cord (T8-T9)failure of legs (paraplegic)
medical term for whiplashspinal shock
bruising of spinal cord, abolition of reflex activity following transection (few days to few weeks)spinal shock
injury to nerve around C5 or C6Erb-Duchenne palsy (waiter's tip)
nerve injury to radial nervewrist drop
injury where fingers are permanently flexedclaw hand
damage to long thoracic nervewinged scapula
injury where you can't flex fingers or rotate handmedial nerve injury

Section 6

Question Answer
system spinal nerves are a part ofPNS
what spinal nerves connect CNS tosensory receptors, muscle, glands
number of cervical nerves8 pairs
number of thoracix nerves12 pairs
number of lumbar nerves5 pairs
number of coccyx nerves1 pair
formed by the axon and its associated glial cellsnerve fiber
smallest layer of a nerve endoneurium
medium sized layer of a nerveperineurium
bundles of nerve fibersfasciculi
largest layer of a nerveepineurium
loose connective tissue layer each nerve fiber sits inendoneurium
composition of endoneuriumcollagen, fibroblasts, some macrophages
connective tissue layer that surrounds fasciculiperineureum
composition of perineureum15 layers of collagen sheaths made up of macrophages and mostly fibroblasts
connective tissue layer that surrounds the whole nerveepineurium

Section 7

Question Answer
anterior and posterior roots run together for a short distance then branch into...dorsal and ventral rami
structure composed of axons of motor (efferent) neurons that emerges from anterior spinal cordanterior (ventral) roots
what the junction of the anterior and postrior root ismixed nerve called spinal nerve trunk
structure composed of sensory axons lying between a spinal nerve and the dorsolateral aspect of the spinal cordposterior (dorsal) roots
a group of cell bodies of sensory neurons and their supporting cells located along posterior rootposterior (dorsal) ganglion

Section 8

Question Answer
branch of a spinal nerveramus
branch that innervates and supplies skin and muscles of the backposterior (dorsal) rami
branch that innervates plexus that supplies anterior trunk and limbsanterior (ventral) rami
branch that supplies meninges, vertebrae, blood vesselsmeningeal branch
branches of spinal nerve that are components of autonomic nervous systemrami communicantes

Section 9

Question Answer
joining of axons from anterior rami of adjacent nerves where nerves meet before they supply body structuresplexus
network formed by nerve axons from ventral rami of first 4 cervical nerves and receive gray rami communicantes from superior cervical ganglioncervical plexus
network of axons of ventral rami of spinal nerves C5, C6, C7, C8, T1brachial plexus
what nerves emerging from brachial plexus supplyupper limb
network of axons formed by anterior (ventral) branches of spinal nerves L1-L4lumbar plexus
network formed by ventral branches of spinal nerves L4-S3sacral plexus
plexus phrenic nerve emerges from and extends to diaphragmcervical
plexus related to breathingcervical
nerves that extend from brachial plexusmedian, ulnar, axillary, musculocutaneous, radial, brachioplexi
innervated by median and ulnar nerveswrist and hand
innervated by axillarydeltoid, teres major
cord axillary comes off ofposterior
innervated by musculocutaneousanterior arm (elbow flexors)
cord radial nerve comes off of posterior
innervated by brachoplexishoulder and upper arm
damage to this nerve causes claw handulnar
damage to this nerve causes wrist dropradial

Section 10

Question Answer
what lumbar plexus suppliesabdominal wall, external genitalia, anterior and medial thigh
damage to this causes inability to extend leg or loss of sensation to thighfemoral
damage to this causes thigh and abductor problems obturator
what plexus does spinal nerve T6 come off of?it doesn't come off of any plexus (trick)
supplied by sacral plexusbutt, perineum, lower limbs
injury to this nerve can cause loss of function to anterior legtibial
nerves that emerge from lumbar plexusfemoral, obtruator
nerves that emerge from sacral plexustibial, sciatic, pudendal
injury to this nerve caused by lumbar vertebrae pressing on each othersciatic
nerve that goes to interior genitalia and leads to penis sensationpudendal
injury to fibular nervefoot drop
collapse of S1 S2 S3 from weight of being on each otherspinal stenoisis

Section 11

Question Answer
2 sensory tractslateral and anterior spinothalamic tracts, posterior columns
tract that carries axons responsible for pain, temperature, deep pressure, crude touch (pressing hard)lateral and anterior spinothalamic tracts
sensations posterior columns are responsible forproprioception, discriminative touch, two-point discrimination, light pressure, vibrations
awareness of the positions and movements of muscles, tendons, and jointsproprioception
the ability to feel exactly where the body is toucheddiscriminative touch
the ability to distinguish the touching of two different points on the skin even if they are close togethertwo-point discrimination

Section 12

Question Answer
direct (motor) pathwayslateral corticospinal, anterior corticospinal, corticobulbar tracts
what direct pathways conveyinformation from the brain about voluntary movements
indirect pathwaysrubrospinal tract, tectospinal tract, vestibulospinal tract, lateral reticulospinal tract, medial reticulospinal tract
what indirect pathways conveynerve impulses from brain stem that govern automatic movements, coordinate body movements with visual stimuli, muslce tone, equilibriu
indirect pathway that programs automatic movements of posture, equilibrium, coordination of visual effectsrubrospinal, tectospinal

Section 13

Question Answer
how spinal cord promotes homeostasisserves as an integrating center for reflexes
where integration of a spinal reflex occursgray matter
where integration of cranial reflex occursbrain stem
reflex that involves contraction of skeletal musclesomatic
reflex that is not visually perceived like stomach growlingautonomic reflex
steps of a reflex arcsensory receptor, sensory neuron, integrating center, motor neuron, effector
where reflex arc of patellar reflex startssensory receptor
what happens at the sensory receptor in patellar reflexstimulus hits muscle spindle, muscles in quad are stimulated
where the integrating center of the reflex arc isCNS gray matter