Lab Exercise 18

Question 1

What are the three protective connective tissue layers around each spinal nerve?

Answer 1

epineurium, perineurium, endoneurium

Question 2

What does the epineurium do?

Answer 2

surrounds the whole nerve

Question 3

What does the perineurium do?

Answer 3

encases each fascicle (bundle of axons)

Question 4

What does the endoneurium do?

Answer 4

covers myelinated and unmyelinated axons

Question 5

What is the posterior ramus?

Answer 5

branch of a spinal nerve that curves around to the dorsal surface and innervates the skin and deep muscles of the back or trunk

Question 6

What is the anterior ramus?

Answer 6

branch that supplies the muscles and skin of all four limbs, as well as the anterior and lateral parts of the body

Question 7

What is the meningeal branch?

Answer 7

serves the vertebrae, vertebral ligaments, blood vessels of the spinal cord, and the meninges

Question 8

How many cervical nerves are there?

Answer 8

8

Question 9

How many thoracic nerves are there?

Answer 9

12

Question 10

How many lumbar nerves are there?

Answer 10

5

Question 11

How many sacral nerves are there?

Answer 11

5

Question 12

How many coccygeal nerves are there?

Answer 12

1

Question 13

What is a plexus?

Answer 13

a braided network of axons from the anterior rami of spinal nerves joining before they innervate body structures

Question 14

What are the 4 plexuses?

Answer 14

cervical, brachial, lumbar, and sacral

Question 15

What does the phrenic nerve do?

Answer 15

innervates the diaphragm and is important for breathing
Cervical nerves 3, 4, 5 keep the diaphragm alive

Question 16

What muscles does the axillary nerve innervate?

Answer 16

deltoid and teres minor

Question 17

What muscles does the musculocutaneous nerve innervate?

Answer 17

anterior muscles of the arm (biceps brachii and brachialis)

Question 18

What muscles does the ulnar nerve innervate?

Answer 18

muscles of anterior forearm (flexor carpi ulnaris, medial-half of flexor digitorum profundis, and most hand muscles)

Question 19

What muscles does the median nerve innervate?

Answer 19

muscles of anterior forearm (excluding flexor carpi ulnaris and medial half of flexor digitorum profundis) and some of the muscles of the hand

Question 20

What muscles does the radial nerve innervate?

Answer 20

muscles of posterior arm (triceps brachii) and posterior forearm (extensors)