Spinal Cord, Spinal Nerves And Somatic Reflexes

Front 1

information highway between brain and body

Back 1

spinal cord

Front 2

where spinal cord extends through

Back 2

vertebral canal from foramen magnum to L1

Front 3

each pair of spinal nerves receives ____ and issues____ to muscles and glands

Back 3

sensory information, motor signals

Front 4

spinal cord is a component of the ___, while the spinal nerves are part of the___

Back 4

cns,pns

Front 5

bundles of fibers passing information up and down spinal cord

Back 5

conduction

Front 6

functions of spinal cord

Back 6

conduction, locomotion, reflexes

Front 7

repetitive, coordinated actions of several muscle groups,

Back 7

locomotion

Front 8

pools of neurons providing control of flexors and extensors

Back 8

central pattern generators

Front 9

involuntary, stereotyped responses to stimuli, involves brain, spinal cord and peripheral nerves

Back 9

reflexes

Front 10

how many pairs of spinal nerves arise from cervical, thoracic, lumbar, and sacral regions of the cord

Back 10

31 pairs

Front 11

tapered tip of spinal cord

Back 11

medullary cone

Front 12

L2 to S5 nerve roots, resembles horse's tail

Back 12

Cauda equinae

Front 13

3 fibrous layers of meninges enclosing spinal cord

Back 13

dura mater, arachnoid mater, pia mater

Front 14

layer of simple squamous epithelium lining dura mater and loose mesh of fibers filled w/ csf(creates subarachnoid space)

Back 14

arachnoid mater

Front 15

delicate membrane adherent to spinal cord, filium terminale and denticulate ligaments anchor the cord

Back 15

pia mater

Front 16

tough collagenous membrane surrounded by epidural space filled w/ fat and blood vessels

Back 16

dura mater

Front 17

neuron cell bodies w/ little myelin

Back 17

gray matter

Front 18

has a pair of dorsal or posterior horns and a pair of bentral or anterior horns

Back 18

gray matter in the spinal cord

Front 19

dorsal root of spinal nerve is totally ...

Back 19

sensory fibers

Front 20

ventral root of spinal nerve is totally ...

Back 20

motor fibers

Front 21

white matter

Back 21

myelinated axons

Front 22

bundles of myelinated axons that carry signals up and down to and from brainstem

Back 22

white column

Front 23

3 pairs of white columns or funiculi

Back 23

dorsal, lateral, and anterior columns

Front 24

each white column is filled w/ ...

Back 24

named tracts or fasciculi

Front 25

fibers w/ a similar origin, destination, and function

Back 25

fasciculi

Front 26

ascending and descending tracts

Back 26

heading up or down

Front 27

decussation

Back 27

means that the fibers cross sides

Front 28

means origin and destination are on opposite sides

Back 28

contralateral

Front 29

means origin and destination are on the same sides

Back 29

ipsilateral

Front 30

carry signals from arm and leg

Back 30

fasciculus gracilis and cuneatus

Front 31

carries signal to cerebral cortex

Back 31

3rd order neuron

Front 32

deep touch, visceral pain, vibration, proprioception

Back 32

dorsal column ascending pathway

Front 33

decussation of 2nd order neuron in medulla

Back 33

dorsal column ascending pathway

Front 34

pain, pressure, temp., light, touch, tickle, and itch occur in this pathway

Back 34

spinothalamic pathway

Front 35

in the spinothalamic pathway, decussation of the _______ occurs in the _______.

Back 35

2nd order, spinal cord

Front 36

in the spinothalamic pathway, ________ arise in the ______ and continure to cerebral cortex.

Back 36

3rd order neurons, thalamus

Front 37

pain signals from tissue infury occur in this

Back 37

spinoreticular tract

Front 38

in spinoreticular tract, decussate in _______ and ___ w/ _____

Back 38

spinal cord, ascend, spinothalamic fibers

Front 39

the spinoreticular tract ends in________

Back 39

reticular formation(medulla and pons)

Front 40

in the spinoreticular tract the _________ continue to ____ and cerebral cortex

Back 40

3rd and 4th order neurons, thalamus

Front 41

in this pathway, _______ signals from limbs and trunk travel up to the _______.

Back 41

spinocerebellar pathway, proprioceptive

Front 42

in the spinocerebellar pathway ____ nerves _____ in _____ lateral column

Back 42

2nd order neurons, ascend, ipsilateral

Front 43

this tract is responsible for precise, coordinated movements

Back 43

corticospinal tract

Front 44

2 neuron pathways of corticospinal tract

Back 44

1. upper motor neuron in cerebral cortex
2. lower motor neuron in spinal cord

Front 45

decussation in medulla

Back 45

corticospinal tract

Front 46

3 descending motor tracts

Back 46

1. tectospinal tract(tectum of midbrain)
2.) reticulospinal tract(reticular formation)
3. vestibulspinal tract(brainstem nuclei)

Front 47

controls limb movements important to maintain posture and balance

Back 47

reticulspinal decending motor tract

Front 48

reflex turning of head in response to sights and sounds

Back 48

tectospinal descending motor tract

Front 49

postural muscle activity in response to inner ear signals

Back 49

vestibulospinal descending motor tract

Front 50

diseases causing destruction of motor neurons and skeletal muscle atrophy

Back 50

poliomyelitis and ALS

Front 51

spread by fecally contaminated water

Back 51

poliomyelitis

Front 52

causes sclerosis of spinal cord due to astrocyte failure to reabsorb glutamate neurotransmitter

Back 52

Amyotroephic Lateral Sclerosis

Front 53

weakness progresses to paralysis and respiratory arrest

Back 53

Poliomyelitis

Front 54

causes paralysis and muscle atrophy

Back 54

ALS

Front 55

a nerve is a bundle of _____

Back 55

fibers(axons)

Front 56

______covers nerves, ______ surrounds a fabiscle, and ______ separates individual nerve fibers

Back 56

epineurium, perneurium, endoneurium

Front 57

in a nerve, blood vessels penetrate only to the ______

Back 57

perineurium

Front 58

ganglia in pns

Back 58

cluster of neuron cell bodies in nerve in pns

Front 59

the ____ ganglion is _____ cell bodies

Back 59

dorsal root, sensory

Front 60

in the dorsal root ganglion of the pns, ____ pass through w/out _____

Back 60

fibers, synapsing

Front 61

how many pairs of spinal nerves

Back 61

31

Front 62

where do mixed nerves in the spinal nerves exit

Back 62

intervertebral foramen

Front 63

proximal branches of spinal nerves

Back 63

dorsal roots, ventral roots, cauda equina roots

Front 64

proximal branch that is the motor input of the spinal cord

Back 64

ventral root

Front 65

proximal branch that is sensory input to spinal cord

Back 65

dorsal root

Front 66

proximal branch w/ roots from L2-CO of the cord(horsetail)

Back 66

cauda equinae

Front 67

distal branches of spinal nerves

Back 67

dorsal ramus, ventral ramus, meningeal branch

Front 68

distal branch to meninges, vertebrae and ligament

Back 68

meningeal branch

Front 69

distal branch that supplies dorsal body muscle and skin

Back 69

dorsal ramus

Front 70

distal branch to ventral skin and muscles and limbs

Back 70

ventral ramus

Front 71

# of cervical spinal nerves

Back 71

8

Front 72

# of thoracic spinal nerves

Back 72

12

Front 73

# of lumbar spinal nerves

Back 73

5

Front 74

# of sacral spinal nerves

Back 74

5

Front 75

# of coccygeal spinal nerves

Back 75

1

Front 76

each spinal nerve receives sensory input from a specific area of skin called

Back 76

dermatome

Front 77

overlap at edges by 50%

Back 77

cutaneous innervation and dermatomes

Front 78

# of succesive spinal nerves it takes to have a total loss of sensation

Back 78

3

Front 79

nature of somatic reflexes

Back 79

quick, involuntary, stereotyped reactions of glands or muscle to sensory stimulation

Front 80

are automatic responses to sensory input that occur w/out our intent or often even our awareness

Back 80

somatic reflexes

Front 81

somatic reflexes function by means of a ______

Back 81

somatic reflex arc

Front 82

somatic reflexes start w/ a ______ of somatic receptors

Back 82

stimulation

Front 83

in somatic reflexes ______ fibers carry signal to ______ of spinal cord

Back 83

afferent, dorsal horn

Front 84

in somatic reflexes, _____ fibers carry impulses to skeletal muscles

Back 84

efferent

Front 85

sense organ(proprioceptor) that monitors length of muscle and how fast muscles change in length

Back 85

muscle spindle

Front 86

the muscle spindle is composed of _______ fibers, _____ fibers and gamma motorneurons

Back 86

intrafuscal muscle, afferent

Front 87

when a muscle is stretched, it contracts and maintains increased tonus (stretch reflex)

Back 87

stretch(myotatic) reflex

Front 88

the stretch(myotatic) reflex helps maintain____and_____

Back 88

equilibrium, posture

Front 89

examples of stretch(myotatic) reflexes

Back 89

head starts to tip forward as you fall asleep, muscles contract to raise the head

Front 90

the stretch(myotatic) reflex _____joints by balancing tension in ______and______ smoothing muscle actions

Back 90

stabilize, extensors and flexors

Front 91

knee-jerk(patellar) reflex

Back 91

monosynaptic reflex

Front 92

why is testing somatic reflexes benefitial to us

Back 92

helps to diagnose many diseases

Front 93

prevents muscles from working against each other in stretch(myotatic) reflex

Back 93

reciprocal inhibition

Front 94

has a polysynaptic reflex arc, occurs during withdrawal of foot from pain

Back 94

flexor withdrawal reflexes

Front 95

in flexor withdrawal reflexes, ______ in spinal cord controls sequence and duration of muscle contractions

Back 95

neural circuitry

Front 96

maintains balance by extending other leg

Back 96

crossed extensor reflexes

Front 97

type of crossed extensor reflex that extends up and down the spinal cord

Back 97

intersegmental reflex

Front 98

this type of crossed extensor reflex arc is explained by pain at one foot causes muscle contraction in other leg

Back 98

contralateral reflex arc

Front 99

in this type of reflex, there are proprioceptors in a tendon near its junction w/ a muscle-1mm long, encapsulated nerve bundle

Back 99

golgi tendon reflex

Front 100

in golgi tendon reflex, ______ on tendon inhibits motor neuron

Back 100

excessive

Front 101

functions when muscle contracts unevenly

Back 101

golgi tendon reflex

Front 102

early symptoms of spinal cord trauma

Back 102

spinal shock

Front 103

in spinal cord trauma, tissue damage at time of injury is followed by _______

Back 103

post-traumatic infarction