Lab Exercise 18 Flashcards
What are the three protective connective tissue layers around each spinal nerve?
epineurium, perineurium, endoneurium
What does the epineurium do?
surrounds the whole nerve
What does the perineurium do?
encases each fascicle (bundle of axons)
What does the endoneurium do?
covers myelinated and unmyelinated axons
What is the posterior ramus?
branch of a spinal nerve that curves around to the dorsal surface and innervates the skin and deep muscles of the back or trunk
What is the anterior ramus?
branch that supplies the muscles and skin of all four limbs, as well as the anterior and lateral parts of the body
What is the meningeal branch?
serves the vertebrae, vertebral ligaments, blood vessels of the spinal cord, and the meninges
How many cervical nerves are there?
8
How many thoracic nerves are there?
12
How many lumbar nerves are there?
5
How many sacral nerves are there?
5
How many coccygeal nerves are there?
1
What is a plexus?
a braided network of axons from the anterior rami of spinal nerves joining before they innervate body structures
What are the 4 plexuses?
cervical, brachial, lumbar, and sacral
What does the phrenic nerve do?
innervates the diaphragm and is important for breathing
Cervical nerves 3, 4, 5 keep the diaphragm alive
What muscles does the axillary nerve innervate?
deltoid and teres minor
What muscles does the musculocutaneous nerve innervate?
anterior muscles of the arm (biceps brachii and brachialis)
What muscles does the ulnar nerve innervate?
muscles of anterior forearm (flexor carpi ulnaris, medial-half of flexor digitorum profundis, and most hand muscles)
What muscles does the median nerve innervate?
muscles of anterior forearm (excluding flexor carpi ulnaris and medial half of flexor digitorum profundis) and some of the muscles of the hand
What muscles does the radial nerve innervate?
muscles of posterior arm (triceps brachii) and posterior forearm (extensors)
