Brain and Spinal Cord Part 4: (Grey and white matter and spinal nerves)

Question 1

1. How is the grey matter shaped

Answer 1

shaped like a butterfly or H-shaped

Question 2

2. What does the grey matter consist of

Answer 2

• consists of nerve cell bodies
• their dendrites
• synaptic connection

Question 3

3. What is the grey matter surrounded by

Answer 3

white matter

Question 4

4. What does white matter in the spinal cord consist of and what are they called

Answer 4

consists of bundles of myelinated and unmyelinated axons called tracts/fasciculi

Question 5

What does the posterior projections of grey matter contain

Answer 5

contain the cell bodies of neurons which incoming sensory neurones synapse with

Question 6

What do the anterior projections of the grey matter contain

Answer 6

contain the cell bodies of outgoing motor neurones

Question 7

what is the name for posterior projections of grey matter

Answer 7

dorsal horns

Question 8

what are the 2 names for anterior projections of grey matter

Answer 8

• anterior horns
  OR
• ventral horns

Question 9

what is found in the centre of grey matter

Answer 9

a hollow central canal

Question 10

1. What are the descending motor tracts of the white matter associated with

Answer 10

Muscle contraction & movement

Question 11

What 4 things is the ascending sensory tracts of the white matter associated with

Answer 11

• Pain
• touch
• temperature
• proprioception

Question 12

1. Where are neuronal cell bodies found

Answer 12

in the grey matter

Question 13

2. What are neuronal cell bodies attach to the spinal cord via

Answer 13

via rootlets

Question 14

3. What are groups of neuronal cell bodies within the PNS called

Answer 14

ganglia

Question 15

4. What are dorsal rootlets

Answer 15

sensory neurones contained in the Dorsal horn

Question 16

5. What do the dorsal rootlets merge to become

Answer 16

dorsal roots with dorsal root ganglia

Question 17

6. What are ventral rootlets

Answer 17

bodies of motor neurones in the Ventral horns

Question 18

What do the dorsal and ventral roots combine to become

Answer 18

the mixed spinal nerve

Question 19

what does the mixed spinal nerve give off

Answer 19

• ventral and dorsal rami
• Meningeal branches & rami communicantes

Question 20

7. What do ventral rootlets combine to become

Answer 20

ventral roots

Question 21

what type of innervation does dorsal roots carry

Answer 21

sensory innervation

Question 22

what type of innervation does ventral roots carry

Answer 22

motor innervation

Question 23

1. How many cervical spinal nerves are there and where do they innervate

Answer 23

• 8 cervical spinal nerves
• They innervate the neck and upper limbs

Question 24

2. How many thoracic spinal nerves are there and where do they innervate

Answer 24

• 12 thoracic spinal nerves
• they innervate the thorax and abdomen

Question 25

How many lumbar spinal nerves are there and where do they innervate

Answer 25

• 5 lumbar spinal nerves
• they innervate lower limbs

Question 26

4. How many sacral spinal nerves are there and where do they innervate

Answer 26

• 5 sacral spinal nerves
• they innervate lower limb and pelvic and perineal regions

Question 27

5. Where does the coccygeal spinal nerve innervate?

Answer 27

the skin over the coccyx