Exam 3

Question 1

Lamina I (marginal zone)

Answer 1

thin layer of gray matter that covers substantia gelatinosa

Question 2

II

Answer 2

Substantia gelatinosa

Question 3

III–VI

Answer 3

Posterior horn body

Question 4

VII

Answer 4

Intermediate grey matter (Clarke’s nucleus)

Question 5

VIII

Answer 5

Interneuronal zone of anterior horn

Question 6

IX

Answer 6

Alpha and gamma motor neuron clusters in anterior horn

Question 7

X

Answer 7

gray matter surrounding central canal

Question 8

Sympathetic neurons anatomy/tract

Answer 8

• Intermediolateral cell column
• T1 to L3

Think of lateral horns on blue picture

Question 9

Parasympathetic neurons anatomy/tract

Answer 9

• Sacral parasympathetic nucleus
• S2 to S4

Horns not as visible; gray picture

Question 10

Proprioceptive info to cerebellum anatomy/tract

Answer 10

• Posterior Thoracic Nucleus (Clarke’s Nucleus)
• T1 to L2

Question 11

which horn contains motor neurons?

Answer 11

anterior horn

Question 12

What neurons innervate the intrafusal muscle fibers of muscle spindles?

Answer 12

gamma/fusimotor neurons

Question 13

how many cranial nerves

Answer 13

12

Question 14

how many cervical nerves

Answer 14

8

Question 15

how many thoracic nerves

Answer 15

12

Question 16

how many lumbar nerves

Answer 16

5

Question 17

how many sacral nerves

Answer 17

5

Question 18

how many coccygeal nerves

Answer 18

1

Question 19

what is the end of the spinal cord called

Answer 19

conus medullaris

Question 20

what anchors spinal cord to dural sac

Answer 20

pia mater

Question 21

where can you perform a spinal tap

Answer 21

cauda equina

Question 22

gray matter forms…

Answer 22

horns

Question 23

white matter forms…

Answer 23

funiculi

Question 24

where does sensory info enter?

Answer 24

posterolateral sulcus

Question 25

where does motor info exit?

Answer 25

anterolateral sulcus

Question 26

which tracts are ascending?

Answer 26

- spinothalamic - spinocerebellar - posterior column-medial lemniscus

Question 27

which tracts are descending

Answer 27

lateral and anterior corticospinal tracts

Question 28

where do large diameter, heavily myelenated afferents enter? | tactile and proprioceptive info

Answer 28

medially through posterior funiculus

Question 29

where do small diameter afferents enter? | pain and temperature

Answer 29

laterally near substantia gelatinosa

Question 30

spinothalamic tract | What does it do? How is it organized?

Answer 30

- pain and temperature - C,T,L,S organization (medial -> lateral)

Question 31

Anterolateral system

Answer 31

- all ascending pain pathways - to thalamus and brainstem ## Footnote Spinothalamic fibers enter substantia gelatinosa, cross anterior commissure, and then ascend anterolateral system

Question 32

spinoreticular tract | part of anterolateral system tracts

Answer 32

modulates pain

Question 33

spinomesencephalic tract | part of anterolateral system tracts

Answer 33

project to periaqueductal gray

Question 34

spinohypothalamic tract | part of anterolateral system tracts

Answer 34

visceral pain response (nausea, etc.) involving hypothalamus

Question 35

is fasciculus gracilis or cuneatus more medial?

Answer 35

gracilis

Question 36

Lissaure's tract | in posterior horn

Answer 36

primary neurons move up and down here before synapsing onto secondary neurons (in substantia gelatinosa)

Question 37

where does the spinothalamic tract terminate?

Answer 37

ventroposterior lateral nucleus of the thalamus

Question 38

lateral corticospinal tract

Answer 38

skilled movements of extremities

Question 39

anterior corticospinal tract

Answer 39

postural adjustment

Question 40

where does the lateral corticospinal tract travel down the spinal column?

Answer 40

lateral column

Question 41

where does the anterior corticospinal tract travel down the spinal column?

Answer 41

anterior column

Question 42

how is the corticospinal tract organized?

Answer 42

C,T,L,S (medial -> lateral)

Question 43

where do descending fibers travek through?

Answer 43

internal capsule

Question 44

are corticospinal fibers ipsilateral or contralateral? | Lateral? Anterior?

Answer 44

Lateral = contralateral Anterior = ipsilateral

Question 45

where does the lateral corticospinal tract decussate?

Answer 45

pyramids

Question 46

where does info from the skin to the brain enter?

Answer 46

dorsal root ganglion

Question 47

how is the posterior column-medial lemniscus tract organized?

Answer 47

S,L,T,C (medial -> lateral) | opposite of other tracts!

Question 48

where does the medial lemnsicus terminate?

Answer 48

ventral posterolateral nucleus of the thalamus

Question 49

what do interneurons in spinal cord do | in terms of reflexes

Answer 49

distinguish a polysynaptic from a monosynaptic reflex

Question 50

Effector

Answer 50

muscle (striated or smooth) or gland