Gray Matter

Question 1

1 + 2 + 3

Answer 1

White matter divided into 3 columns, each containing fiber tracks, composed of axons with similar functions

1. posterior funiculus
2. lateral funiculus
3. anterior funiculus

Question 2

4

Answer 2

anterior white commissure

Question 3

5

Answer 3

dorsal horn (or posterior horn)

• interneurons

Question 4

6

Answer 4

lateral horn

• contain sympathetic nerve fibers

Question 5

7

Answer 5

ventral horn (or anterior horn)

• interneurons + somatic motor neurons
• if damaged, flaccid paralysis results.

Question 6

8

Answer 6

gray commissure

• connects masses of gray matter
• encloses the central canal

Question 7

11

Answer 7

dorsal intermediate sulcus

Question 8

12

Answer 8

dorsal lateral sulcus

Question 9

13

Answer 9

ventral lateral sulcus

Question 10

23

Answer 10

dorsal root (sensory roots)

Question 11

24

Answer 11

dorsal root ganglion

Question 12

25

Answer 12

ventral root ganglion (motor roots)

Question 13

26

Answer 13

spinal nerves

• the dorsal and ventral roots fuse laterally to form the spinal nerves
• there are 31 pairs attached to the cord by paired roots

Question 14

27

Answer 14

dorsal ramus of spinal nerve

Function: sensory/motor innervation to skin and back muscles

Question 15

28

Answer 15

ventral ramus of spinal nerve

Function: sensory/motor innervation to ventral/lateral body surface/skin, body wall/trunk, limb muscles

Question 16

29 + 30

Answer 16

rami communicantes

Function: signals to and from the autonomic nervous system;
innervation to viscera - cardiac and smooth muscle

Question 17

A

Answer 17

dorsal median sulcus (or posterior median sulcus)

• divides the posterior funiculi

Question 18

B

Answer 18

ventral median fissure (or anterior median fissure)

• separates the anterior funiculi

Question 19

C

Answer 19

central canal

Question 20

D

Answer 20

somatic sensory neurons (afferent)

Question 21

E

Answer 21

visceral sensory neurons (afferent)

Question 22

F

Answer 22

visceral motor neuron (efferent)

Question 23

G

Answer 23

somatic motor neuron (efferent)

Question 24

What does gray matter consist of?

Answer 24

1. soma
2. unmyelinated processes
3. neuroglia