chapter 13 spinal cord,Nerves,somatic reflex

Question 1

Spinal cord

Answer 1

cylinder of nervous tissue that arises from the brainstem at the foramen magnum of the skull

Question 2

Segment

Answer 2

part of the spinal cord supplied by each pair of spinal nerves

Question 3

Medullary cone

Answer 3

T11-L3

Question 4

Cauda equina

Answer 4

nerve roots L2 to S5

Question 5

Meninges

Answer 5

three fibrous membranes that enclose the brain and spinal cord

Question 6

Dura mater

Answer 6

-Forms loose-fitting sleeve (dural sheath) around spinal cord
Tough, thick membrane of dense irregular connective tissue

Question 7

Epidural space

Answer 7

space between dura and vertebral bones; contains blood vessels, adipose tissue, loose connective tissue

Question 8

Arachnoid mater

Answer 8

arachnoid membrane adhering to dura and is separated from pia by fibers spanning the subarachnoid space that is filled with cerebrospinal fluid (CSF

Question 9

Pia mater:

Answer 9

Fuses with dura to form coccygeal ligament

Question 10

Gray matter

Answer 10

emotions, memory, control of movement

Question 11

white matter

Answer 11

body processing information

Question 12

(dorsal) horns

Answer 12

receive somatosensory nerve fibers,

Question 13

(ventral) horns

Answer 13

skeletal muscle

Question 14

lateral horns

Answer 14

T2 through L1, (Visceral and Pelvic organs)

Question 15

Marginal Zone

Answer 15

Relay Pain and Temp to Brain

Question 16

Substantia Gelatinosa

Answer 16

Relay Pain, Temp, and Light Touch to Brain

Question 17

Dorsal Nucleus of Clarke

Answer 17

-Unconscious proprioceptive information to the brain
-Only found in C8 to L3

Question 18

Nucleus Proprius

Answer 18

Mechanical and Temp sensation to Brain

Question 19

Intermediolateral Nucleus

Answer 19

sensory information from viscera to the brain, and autonomic signals from the brain to the visceral organs

Question 20

Lateral/Medial Motor Neurons

Answer 20

Motor neurons that innervate visceral and skeletal muscles.

Question 21

Ascending tracts

Answer 21

information goes UP(sensory)

Question 22

Descending tracts

Answer 22

information goes DOWN (motor)

Question 23

Gracile fasciculus

Answer 23

carries signals up from midthoracic and lower parts of body

Question 24

Cuneate fasciculus

Answer 24

carries signals up from chest and upper limbs

Question 25

Spinothalamic tract

Answer 25

-part of the anterolateral system,Carries signals for pain, pressure, temperature, light touch, tickle, and itch

Question 26

First-order neurons

Answer 26

end in posterior horn of spinal cord

Question 27

Second-order neurons

Answer 27

posterior horn, then decussate and form the spinothalamic tract

Question 28

Third-order

Answer 28

neurons continue from secound to cerebral cortex

Question 29

Spinoreticular tract

Answer 29

Carries pain signals resulting from tissue injury

Question 30

posterior/anterior spinocerebellar tracts

Answer 30

Carry proprioceptive signals from limbs and trunk up to the cerebellum

Question 31

Upper motor neuron

Answer 31

in cerebral cortex or brainstem

Question 32

Lower motor neuron

Answer 32

cell body is in brainstem or spinal cord

Question 33

Lateral/anterior (ventral) corticospinal tracts

Answer 33

precise, finely coordinated movements

Question 34

lower medulla

Answer 34

Most fibers decussate in.....

Question 35

tectospinal tract

Answer 35

Functions in reflex turning of head in response to sights and sounds

Question 36

Lateral/ medial reticulospinal tracts

Answer 36

DESCENDING analgesic pathways that regulate transmission of pain signals to brain

Question 37

Lateral/medial vestibulospinal tracts

Answer 37

control extensor muscles of limbs for balance control

Question 38

Poliomyelitis

Answer 38

-Caused by the poliovirus -Destroys motor neurons in brainstem and anterior horn of spinal cord -muscle pain, weakness, and loss of some reflexes paralysis, muscular atrophy, and respiratory arrest -Virus spreads by fecal contamination of water

Question 39

Amyotrophic lateral sclerosis (ALS) or Lou Gehrig disease

Answer 39

-Destruction of motor neurons and muscular atrophy -Also sclerosis (scarring) of lateral regions of the spinal cord -Early signs: muscular weakness; difficulty speaking, swallowing, and using hands -Sensory and intellectual functions remain unaffected

Question 40

Nerve

Answer 40

a cord-like organ composed of numerous nerve fibers (axons) bound together by connective tissue

Question 41

Sensory nerves

Answer 41

composed only of afferent fibers; carry signals from sensory receptors to the CNS Rare, include nerves for smell and vision

Question 42

Motor nerves

Answer 42

carry signals from CNS to muscles and glands

Question 43

mixed nerves

Answer 43

consist of both afferent and efferent fibers Most common type

Question 44

Ganglion

Answer 44

cluster of nerve cell bodies outside the CNS

Question 45

7 cervical (C1 to C7) 12 thoracic (T1 to T12) 5 lumbar (L1 to L5) 5 sacral (S1 to S5) 1 coccygeal (Co1)

Answer 45

31 spinal nerves

Question 46

Posterior (dorsal) root

Answer 46

sensory input to spinal cord

Question 47

Anterior (ventral) root

Answer 47

motor output out of spinal cord

Question 48

Anterior ramus:

Answer 48

gives rise to an intercostal nerve

Question 49

Posterior ramus

Answer 49

innervates the muscles and joints in that region of the spine and the skin of the back

Question 50

Meningeal branch

Answer 50

reenters the vertebral canal and innervates the meninges, vertebrae, and spinal ligaments

Question 51

Chickenpox (varicella)

Answer 51

remains for life in the posterior root ganglia; kept in check by the immune system -caused by varicella-zoster

Question 52

Shingles (herpes zoster)

Answer 52

caused by the virus traveling down the sensory nerves by fast axonal transport when immune system is compromised