Spinal Cord and Ganglia

Question 1

Nerves near vertebrae?

Answer 1

dorsal (sensory) and ventral (motor) root
dorsal root ganglion – thickening of nerve
denticulate ligament – anchors dura to cord

Question 2

What is the somatic reflex arc?

Answer 2

1) receptor
2) sensory neuron (cell body in dorsal root ganglion)
3) integrating center – in spinal cord
4) motor neuron (leaves spinal cord)
5) effector

Question 3

Gray and White matter of spinal cord?

Answer 3

central canal
ventral horn (fatter)
dorsal horn (thinner)
gray commissure (unmyelinated) - btwn dorsal
ventral fissure - btwn ventral

Question 4

Gray and White matter at segments of spinal cord?

Answer 4

cervical - normal
thoracic - small gray matter (less neurons)
lumbar - large gray matter (more neuons)

Question 5

Cell types in spinal cord?

Answer 5

neuropil
motoneurons (large, in ventral horn)
ependymal cells line central canal (secrete CSF)

Question 6

Dorsal root ganglion?

Answer 6

sensory neurons
satellite cells (glial)
no neuropil and no synapses

Question 7

Sympathetic ganglion?

Answer 7

cell body with dendrites
neuropil

Question 8

What is a myotome vs dermatome?

Answer 8

• muscle innervated by specific segment
• area of skin innervated by specific segment

Question 9

Components of autonomic reflex arc?

Answer 9

pre-ganglionic – leave spinal cord (myelin)
para-vertebral ganglion and visceral ganglion
post-ganglionic – travel to gland (unmylein)

Question 10

parasympathetic and sympathetic share nerves with somatic nervous system

Answer 10

spillover of excitation of autonomic to somatic