Spinal cord

Question 1

What receptors are non encapsulated?

Answer 1

Free nerve endings, merkel’s disk, and hair follicles

Question 2

What receptors are encapsulated?

Answer 2

Meissner’s corpuscle, pcinian corpuscle, ruffini ending, joint receptor, neuromuscular spindle, golgi tendon organs

Question 3

What is the function of free nerve endings?

Answer 3

pain/temperature, slow adapting

Question 4

What is the function of merkel’s disk?

Answer 4

touch, slow adapting

Question 5

What is the function of hair follicles?

Answer 5

touch, fast adapting

Question 6

What is the function of meissner’s corpuscle?

Answer 6

2 point discrimination, fast adapting

Question 7

What is the function of pacinian corpuscle?

Answer 7

vibration, fast adapting

Question 8

What is the function of ruffini ending?

Answer 8

stretch, pressure, slow adapting

Question 9

What is the function of joint receptor?

Answer 9

joint position, slow adapting

Question 10

What is the function of neurmuscular spindle?

Answer 10

limb muscle, strength/length, slow adapting

Question 11

What is the function of golgi tendon organs?

Answer 11

muscle tension, slow adapting

Question 12

Describe the lateral division of the dorsal root afferents

Answer 12

thin, lightly myelinated fibers, pain and temp, light touch, visceral afferents

Question 13

Describe the medial division of dorsal root afferents

Answer 13

thick, heavily mylenitaed fibers, 2 point touch, limb position, muscle stretch, sends collaterals to medulla

Question 14

What are the spinal segments?

Answer 14

Cervical: 1-8
Thoracic: 1-12
Lumbar: 1-5
Sacral: 1-5
Coccygeal: 1

Question 15

How far does the fetal cord extend?

Answer 15

to L3

Question 16

What gives the denituclate ligament?

Answer 16

Pia matter; anchors the cord to the dura

Question 17

What are the short/long pre/post ganglionic rules?

Answer 17

1. Parasympathetics have long pre and short post
2. Sympathetics have short pre and long post EXCEPT splanchnics: greater synapses in celiac, less in superior mesenteric and aortico renal, and least in renal plexus

Question 18

Somites in the embryo become what?

Answer 18

Dermis, muscle, skeleton

Question 19

What are the common dermatomal references?

Answer 19

C2: back of head
C6: thumb and index finger
T4: nipples
T10: umbilicus
L3: kneecap
S1: lateral foot

Question 20

Where does the dorsal root enter?

Answer 20

posterior lateral sulcus

Question 21

What is the separation between gracilus and cuneatus?

Answer 21

posterior intermediate sulcus

Question 22

Where is the anterior spinal artery?

Answer 22

anterior median fissure

Question 23

Where does the ventral root leave?

Answer 23

anterior lateral sulcus

Question 24

What makes up the posterior funiculus?

Answer 24

white matter ascending acons mostly from the dorsal column pathway

Question 25

What happens in the dorsolateral fasciculus/zone of lissauer?

Answer 25

area where axons ascend or descend several segments

Question 26

What happens at the anterior commissure?

Answer 26

fibers cross from one side to the other

Question 27

What are the three grey matter regions in the spinal cord?

Answer 27

anterior horn, intermediate gray, and posterior horn

Question 28

What is the substantia gelatinosa?

Answer 28

small compact cells that modify sensory input by synapsing on dendrites in nucleus proprius. Recieves small diamter dorsal root afferents. All cord levels

Question 29

What is the nucleus proprius?

Answer 29

proper sensory nucleus, recieves many sensory inputs and contains main interneurons, contains tract cells that project contralaterally as the spinthalamic tract. all cord levels

Question 30

What is the nucleus dorsalis?

Answer 30

Clark's nucleus. C8-L3. Homologous to the lateral cuneate nucleus in the medulla. recieves muscle spindle information. projects ipsilaterally to the cerebellum as the dorsal spinocerebellar tract.

Question 31

What is the intermediolateral nucleus?

Answer 31

Origin of preganglionic cholinergic sympathetic efferents. T1-L3. GVE

Question 32

What is the intermediomedial nucleus?

Answer 32

recieves visceral afferents, projects to the IML, found at all spinal cord levels

Question 33

What are the medial and lateral motor nuclei?

Answer 33

made up of large alpha motor nueorns that innervate skeletal muscle. Phrenic nucleus exists at c3-c5 in the medial n (cervical ventral horn). spinall accessory n exists at c1-6 laterally.

Question 34

Where are motor nuclei largest?

Answer 34

in the cervical and lumbar enlargements