The Peripheral Nervous System - Chapter 13 - Part 3
How many pair of cranial nerves are there?
12 pair
How many pair of spinal nerves are there?
31 pair
How many cervical nerves are there and name them.
There are 8 cervical nerves. C1-C8
How many thoracic nerves are there and name them.
There are 12 thoracic nerves. T1-T12
How many lumber nerves are there and name them.
There are 5 lumbar nerves. L1-L5
How many sacral nerves are there and name them.
There are 5 sacral nerves. S1-S5
How many coccygeal nerves are there and name them.
There is 1 coccygeal nerve. C1
How many plexus are there and name them.
There are 4 plexus.
1. Cervical plexus
2. Brachial plexus
3. Lumbar plexus
4. Sacral plexus
Which region does NOT have a plexus?
The thoracic
Each spinal nerve connects to the spinal cord via two roots. Name these two roots.
1. Ventral root
2. Dorsal root
Ventral roots contain ____ fibers from the ventral horn motor neurons.
motor (efferent)
The fibers from the ventral root innervate ____?
skeletal muscles
Dorsal roots contain ____ fibers from sensory neurons in the dorsal root ganglia.
sensory (afferent)
Dorsal roots conduct impulses (to or from) peripheral receptors?
from
Dorsal and ventral roots unite to form ____, which then emerge from the vertebral column via the ____ ____.
spinal nerves
intervertebral foramina
Each spinal nerve branches into mixed ____.
rami
All ventral rami except ____ form interlacing nerve networks called ____.
T2-T12
plexuses
The back is innervated by ____ rami via several branches.
dorsal
The ventral rami of T2-T12 are ____ nerves that supply muscles of the ____, ____, and ____.
intercostal
ribs
anterolateral thorax
abdominal wall
White rami do NOT extend below ____ or above ____.
below L2
above T1
The cervical plexus is formed by ____ rami of ____.
ventral
C1-C4
Cervical plexus innervates skin and muscles of the ____, ____, ____, and ____.
neck
ear
back of head
and shoulders
The ____ nerve is the major motor and sensory nerve of the ____. It receives fibers from C__ -C___.
phrenic nerve
diaphragm
C3-C5
Name the four nerves of the cutaneous branches (superficial) and their spinal roots (ventral rami)
lesser occipital, C2 (C3)
greater auricular, C2 C3
transverse cervical, C2 C3
supraclavicular (medial, intermediate, and lateral) C3 C4
The lesser occipital nerve serves the skin on ____
skin on posterolateral aspect of neck
The greater auricular nerve serves the skin of ____
skin of ear, skin over parotid gland
The transverse cervical nerve serves the skin on ___
anterior and lateral aspect of neck
The supraclavicular nerve serves the skin of ____
shoulder and clavicular region
Name the three nerves of motor branches (deep)
ansa cervicalis (superior and inferior roots), C1-C2
segmental and other muscular branches, C1-C5
phrenic, C3-C5
The ansa cervicalis nerve serves the ____
infrahyoid muscles of neck
The segmental nerve serves the ____
deep muscles of neck
The phrenic nerve serves the ____
diaphragm
The brachial plexus is formed by ____ rami of ____-____ and ____ (and often ____ and ____)
ventral rami
C5-C8 and T1
and often C4 and T2
The brachial plexus gives rise to the nerves that innervate the ____
upper limb
What are the four major branches of the brachial plexus?
Roots
Trunks
Divisions
Cords
There are ____ roots (ventral rami). They are located at ____-____.
5 roots
C5-T1
Name the three trunks of the brachial plexus
Upper
Middle
Lower
Name the two divisions of the brachial plexus
anterior and posterior
Name the three cords of the brachial plexus
Lateral
Medial
Posterior
Name 5 nerves of the brachial plexus
Axillary
Musculocutaneous
Median
Ulnar
Radial
The axillary nerve innervates ____, ____, and ____.
deltoid, teres minor, and skin and joint capsule of the shoulder
The musculocutaneous nerve innervates ___, ___, and ___.
biceps brachii, and brachialis and skin of lateral forearm
The median nerve innervates the ____, ____, and ____.
skin, most flexors and pronators in the forearm and some intrinsic muscles of the hand
The ulnar nerve supplies the ____, ____, ____ and ____.
flexor carpi ulnaris, part of the flexor digitorum profundus, most intrinsic muscles of the hand, and skin of medial aspect of hand
The radial nerve innervates ____, ____ and ____.
essentially all extensor muscles, supinators, and posterior skin of limb