spinal cord

Question 1

• lies within the spinal cavity and extends from the foramen magnum to the lower border of the first lumbar vertebra - oval cylinder that tapers slightly as it descends - 2 bulges, one in cervical region and one in lumbar region

Answer 1

structure of the spinal cord

Question 2

the 2 bulges in the spinal cord are called:

Answer 2

• cervical enlargement - lumbar enlargement

Question 3

the anterior median fissure and the posterior median sulcus are two deep grooves; _____ fissure is deeper and wider

Answer 3

anterior

Question 4

cervical enlargement extends from ___ to ___.

Answer 4

C4 to T1

Question 5

lumbar enlargement extends ____ to ____.

Answer 5

T9 to T12

Question 6

termination of the spinal cord. Tapers in a cone shape and ends at the level of the intervertebral disc between L1-2

Answer 6

Conus Medullaris

Question 7

2 bundles of nerve fibers project from each side of the spinal cord are called

Answer 7

nerve roots

Question 8

• carry sensory info into the spinal cord

Answer 8

fibers of dorsal (posterior) nerve root

Question 9

cell bodies of these sensory neurons make up a small region of gray matter called:

Answer 9

dorsal root ganglion

Question 10

• carry motor info out of the spinal cord

Answer 10

fibers of ventral (anterior) nerve root

Question 11

cell bodies of these motor neurons are located in the ______ of the spinal cord

Answer 11

gray matter

Question 12

_____ are located in the spinal cord’s gray matter core

Answer 12

interneurons

Question 13

on each side of the spinal cord, the dorsal and ventral nerve roots join together to form a single mixed nerve called a:

Answer 13

spinal nerve

Question 14

the spinal cord ends at:

Answer 14

L1

Question 15

bundle of nerve roots extending from the conus medullaris at the inferior end of the spinal cord

Answer 15

cauda equina

Question 16

_____ consists predominantly of cell bodies of interneurons and motor neurons and extend the length of the cord

Answer 16

gray matter

Question 17

the left and right gray columns are joined in the middle by a band called the:

Answer 17

gray commissure

Question 18

_____ carries CSF through the spinal cord

Answer 18

central canal

Question 19

white matter surrounds gray matter and is subdivided in each half of the cord into three columns (funiculi):

Answer 19

• ant - post - lat white columns

Question 20

Each white column consists of a large bundle of axons divided into tracts. Names of spinal tracts indicate:

Answer 20

• location of the tract - structure in which the axons originate - structure in which they terminate

Question 21

2 main functions of the spinal cord:

Answer 21

• provides conduction routes to and from the brain - serves as the integrator, or reflex center for all spinal reflexes

Question 22

• conduct sensory impulses up the cord to the brain

Answer 22

ascending tracts

Question 23

• conduct motor impulses down the cord from the brain

Answer 23

descending tracts

Question 24

tracts are both ____ and ____ organizations of nerve fibers composed of bundles of axons

Answer 24

structural and functional

Question 25

ascending tract that deals with crude touch, pain, and temperature

Answer 25

lateral spinothalamic

Question 26

ascending tract that deals with crude touch and pressure

Answer 26

anterior spinothalamic

Question 27

ascending tract that deals with discriminating touch and conscious kinesthesia

Answer 27

posterior column-medial lemniscus

Question 28

ascending tract that deals with subconscious kinesthia

Answer 28

spinocerebellar

Question 29

ascending tract that deals with touch that triggers visual reflexes

Answer 29

spinotectal

Question 30

descending tract that deals with voluntary movements on opposite side of the body (decussate in the medulla)

Answer 30

lateral corticospinal

Question 31

descending tract that deals with voluntary movements on opposite side of the body

Answer 31

anterior corticospinal

Question 32

descending tract that maintains posture during movement

Answer 32

reticulospinal

Question 33

descending tract the transmits impulses that coordinate body movements and maintenance of posture (conveys impulses from the red nucleus)

Answer 33

rubrospinal

Question 34

descending tract that moves head, eyes and trunk in response to visual or auditory stimuli

Answer 34

tectospinal

Question 35

conveys impulses from vestibular nucleus to ipsilateral skeletal muscles of trunk and proximal parts of limbs for posture and balance in response to head movements

Answer 35

vestibulospinal

Question 36

for the cerebral cortex to perform its sensory functions, impulses must first be conducted to sensory areas via relays of neurons referred to as:

Answer 36

sensory pathways

Question 37

each side of the brain registers sensations from the opposite side of the bosy

Answer 37

crossed pathways

Question 38

impulses are conducted from motor areas to skeletal muscles via motor neurons by:

Answer 38

somatic motor pathways

Question 39

the cardinal principle about somatic motor pathways:

Answer 39

principle of the final common path

Question 40

each motor neuron from the anterior gray horn (ventral horn) of the spinal cord conducts impulses to a specific motor unit within a skeletal muscle. axons from the anterior gray horn (ventral horn) are the only ones that terminate in skeletal muscle cells

Answer 40

principle of the final common path

Question 41

any condition that makes ventral horn motor neurons unable to conduct impulses also makes skeletal muscle cells supplied by these neurons unable to contract.

Answer 41

clinical significance of somatic motor pathways

Question 42

- fibers converge in medulla - AKA corticospinal tracts - important for stimulation and precise control of voluntary muscle function

Answer 42

pyramidal tracts

Question 43

- much more complex than pyramidal tracts - all motor tracts from the brain to spinal cord - ventral horn motor neurons except corticospinal tracts - important in larger, automatic movements - sequencing or simultaneous contraction of muscle group

Answer 43

extrapyramidal tracts

Question 44

\_#\_% of corticospinal tracts are pyramidal, lateral and anterior corticospinal tracts voluntary movement

Answer 44

90

Question 45

\_#\_% of corticospinal tracts are extrapyramidal. They are more reflexive and automatic

Answer 45

10

Question 46

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Question 48

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Question 49

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Question 50

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Question 51

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Question 52

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Question 53

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Question 54

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