U4 lecture 30

Question 1

where do enlargements occur

Answer 1

where nerves supply limbs

Question 2

what is a plexus

Answer 2

a location lateral to the spinal cord where spinal nerves from different segments can rejoin

Question 3

what occurs at the cervical enlargement

Answer 3

C4-T1: nerves that it here supply the shoulder girdle and upper limbs

Question 4

what occurs at the lumbar enlargement

Answer 4

T9-T12: nerves that exit here supply the pelvis and lower limbs

Question 5

what occur at the cauda equina

Answer 5

extension of nerves exiting from end of spinal cord

Question 6

what is the distribution of spinal nerves

Answer 6

• cervical enlargement
• lumbar enlargement
• cauda equina

Question 7

where does the cavity for a spinal tap form

Answer 7

at the end of L2 and dura and arachnoid layers that extend to S2

Question 8

where does CSF flow

Answer 8

subarachnoid space

Question 9

what creates the epidural space

Answer 9

the dura mater not being attached to the bony vertebral column

Question 10

what is the central canal of the spinal cord (gray matter)

Answer 10

small opening in center of SC, contains CSF

Question 11

what is the posterior horns of the spinal cord (gray matter)

Answer 11

cell bodies of somatic and visceral sensory neurons

Question 12

what does the gray commisure of the spinal cord do (gray matter)

Answer 12

connects posterior horns

Question 13

what are the anterior horns of the spinal cord (gray matter)

Answer 13

cell bodies of somatic motor neurons

Question 14

what are the lateral horns of the spinal cord (gray matter)

Answer 14

cell bodies of visceral motor neurons found only in thoracic lumbar and sacral regions of spinal cord

Question 15

what are the anterior columns of the spinal cord (white matter)

Answer 15

motor tracts (descending)

Question 16

what does the anterior white commisure of the spinal cord do (white matter)

Answer 16

connects white matter on the left and right side of spinal cord

Question 17

what does the dorsal root of the spinal nerve do

Answer 17

carries afferent (sensory) information

Question 18

what is the dorsal root ganglion

Answer 18

a cluster of sensory cell bodies outside the CNS

Question 19

what does the ventral root of the spinal cord do

Answer 19

carries motor (efferent) information from the anterior portion of the cord

Question 20

what are the spinal nerves and what do they do

Answer 20

joins dorsal and ventral roots; only ~2 cm long; are mixed nerves in that they contain both sensory and motor information. 31 pairs of spinal nerves exit the cord

Question 21

is the lateral corticospinal tract ascending or descending

Answer 21

motor descending tract