Lecture 11 9/26/23

Question 1

What are the characteristics of the CNS?

Answer 1

-surrounded by bone
-includes brain and spinal cord

Question 2

What are the characteristics of the PNS?

Answer 2

-includes cranial and spinal nerves
-12 pairs of cranial nerves
-35 pairs of spinal nerves

Question 3

What is the spinal nerve formula?

Answer 3

-C8T13L7S3Cd4-5

Question 4

What are the characteristics of efferent fibers?

Answer 4

-away from CNS
-motor fibers

Question 5

What are the characteristics of afferent fibers?

Answer 5

-towards CNS
-sensory fibers

Question 6

What are the types of neurons?

Answer 6

-multipolar; efferent; motor
-bipolar; afferent; sensory
-pseudounipolar; afferent; sensory

Question 7

What are the types of efferent fibers?

Answer 7

-general somatic efferent (GSE)
-general visceral efferent (GVE)
-special visceral efferent (SVE)

Question 8

What are the characteristics of GSEs?

Answer 8

-motor to skeletal m.
-found in some cranial nerves and all spinal nerves

Question 9

What are the types of afferent fibers?

Answer 9

-general somatic afferent (GSA)
-general visceral afferent (GVA)
-special somatic afferent (SSA)
-special visceral afferent (SVA)

Question 10

What are the characteristics of GSAs?

Answer 10

-talk with GSEs
-receptors near body surface
-sense touch, temp., and pain
-some cranial nerves and all spinal nerves

Question 11

What are the cauda equina?

Answer 11

nerves that must travel down to their exits; form a “horse tail”

Question 12

What are intumescences?

Answer 12

swellings in the spinal cord where the limbs arise that account for the neuronal cell bodies that innervate the limbs

Question 13

Where do the cervical nerves exit?

Answer 13

in front of the vertebrae with the same number

Question 14

Where do the thoracic nerves exit?

Answer 14

behind the vertebrae with the same number

Question 15

Where does cervical nerve 8 exit?

Answer 15

in front of T1/behind C7

Question 16

Why must the caudal equina nerves run down to their exits?

Answer 16

the spinal cord ends short and does not reach the exits

Question 17

What is the spinal nerve?

Answer 17

where the dorsal and ventral roots meet

Question 18

Where is the dorsal root ganglion located?

Answer 18

within the dorsal root

Question 19

Where does the dorsal branch go?

Answer 19

to the epaxial structures

Question 20

Where does the ventral branch go?

Answer 20

to the hypaxial structures

Question 21

Which type of neuron is in the dorsal root ganglia?

Answer 21

pseudounipolar (GSAs and GVAs)

Question 22

Which type of fibers are found in the dorsal root?

Answer 22

sensory only

Question 23

Which type of fibers are found in the ventral root?

Answer 23

motor only

Question 24

Which types of fibers are found in the spinal nerve, dorsal branch, and ventral branch?

Answer 24

sensory and motor