Anatomy_Key Terms_Ch14 Flashcards
(188 cards)
1
Q
sensory receptors
A
pick up stimuli from inside and outside the body and then initiate impulses in sensory axons, which carry the impulse to the CNS
2
Q
nerves
A
bundles of peripheral axons
3
Q
motor endings
A
terminal boutons of motor neurons that innervate the effector organs, muscles, and glands
4
Q
peripheral sensory receptors
A
structures that pick up sensory stimuli and then initiate signals in the sensory axons; most fit into two main categories: free nerve endings of sensory neurons and complete receptor cells
5
Q
exteroceptors
A
sensitive to stimuli arising outside the body; most located at or near the body surface and include receptors for touch, pressure, pain, and temperature in the skin and most receptors of the special sense organs
6
Q
interoceptors
A
aka veseroceptors, receive stimuli from the internal viscera e.g. digestive tube, bladder, and lungs; different ones monitor a variety of stimuli, including changes in chemical concentration, taste stimuli, the stretching of tissues, and temperature; their activation causes us to feel visceral pain, nausea, hunger, orfullness
7
Q
proprieceptors
A
located in the musculoskeletal organs, e.g. skeletal muscles, tendons, joints, and ligaments; monitor the degree of stretch of these locomotory organs and send input on body movemeents to the CNS
8
Q
mechanoreceptors
A
respond to mechanical forces such as touch, pressure, stretch, and vibrations
9
Q
baroreceptor
A
mechanoreceptor that monitors blood pressure
10
Q
thermoreceptors
A
respond to temperature changes
11
Q
chemoreceptors
A
respond to chemicals in solution (such as molecules tasted or smelled) and to changes in blood chemistry
12
Q
photoreceptors
A
in the eye respond to light
13
Q
nociceptors
A
(noci=harm), respond to harmful stimuli that result in pain
14
Q
general sensory receptors
A
nerve endings of sensory neurons that monitor touch, pressure, vibration, stretch, pain, temperatur, and proprioception; two broad groups: free nerve endings and encapsulated nerve endings surrounded by a capsule of connective tissue
15
Q
free nerve endings
A
invade almost all tissues of the body but are particularly abundant in epithelia and in the connective tissue that underlies epithelia; primarily nociceptors and thermoreceptors; monitor the affective sense, those to which people have an emotional response
16
Q
epithelial tactile complexes
A
aka Merkel discs, lie in the epidermis of the skin; each consists of a disc-shaped tactile epithelial cell innervated by a sensory nerve ending
17
Q
slowly adapting mechanoreceptors
A
continue to respond and send out action potentials even after a long period of contiual stimulation
18
Q
hair follicle receptors
A
free nerve endings that wrap around hair follicles, mechanoreceptors for light touch that monitor the bending of hairs (rapidly adapting)
19
Q
rapidly adapting
A
sensation disappears quickly even if the stimulus is maintained
20
Q
encapsulated nerve endings
A
consist of one or more end fibers of sensory neurons enclosed in a capsule of connective tissue
21
Q
tactile corpuscles
A
“aka Meissner’s corpuscle, a few spiraling nerve endings are surrounded by Schwann cells, which in turn are surrounded by an egg-shaped capsule of connective tissue; occur in the dermal papillae beneath the epidermis; rapidly adapting receptors for fine, discriminative touch; mainly occur in sensitive and hairless areas of the skin e.g. soles, palms, fingertips, nipples, lips”
22
Q
lamellar corpuscles
A
aka Pacinian corpuscles, scattered throughout the deep connective tissues of the body e.g. in the subcutaneous tissue deep to the skin; respond only to the initial application of pressure before they tire and stop firing (rapidly adapting receptors), best suited to moitory vibration; ~0.5-1mm wide and 1-2mm long
23
Q
bulbous corpuscles
A
aka Ruffini endings, located in the dermis and elsewhere, contain an array of nerve endings enclosed in a thin, flattened capsule; adapt slowly and thus can monitory continuous pressure placed on the skin
24
Q
proprioceptors
A
virtually all are encapsulated nerve endings that monitor stretch in the locomotory organs; include muscle spindles, tendon organs, and joint kenesthetic receptors
25
muscle spindles
(neuromuscular spindles), measure the changing length of a muscle as that muscle contracts and is stretched back to its original length; an average muscle contains 50-100, which are embedded in the perimysium between tho fascicles
26
intrafusal muscle fibers
(intra=within, fusal=the spindal), each spindle contains several modified skeletal muscle fibers surrounded by a connective tissue capsule
27
extrafusal muscle fibers
(extra=outside), the ordinary muscle cells outside the spindles, have more striations that the intrafusal muscle fibers
28
anulospiral endings
aka primary sensory endings, twirl around the noncontractile middle of the intrafusal fibers innervating the spindle center; these receptors are stimulated by the rate and degree of stretch of the muscle spindle
29
flower spray endings
(secondary sensory endings), monitor the spindle ends (the only contractile parts of the spindle) and respond only to degree of stretch
30
alpha efferent neurons
spinal motor neurons that cause the entire muscle (extrafusal fibers) to generate conractile force and resist further stretch
31
gamma efferent neurons
neurons preset the sensitivity of the spindle to stretch, most active when balance reflexes must be razor sharp
32
tendon organs
aka Golgi tendon organs, proprioceptors located near the muscle-tendon junction, where they monitor tension within tendons; each consists of an encapsulated bundle of tendon fibers (collagen fibers) whithin wihch sensory nerve endings are intertwined; relaxation reflex is important in motor activities that involve rapid alternation between flexion and extension
33
joint kinesthetic receptors
"""movement feeling"", proprioceptors that monitor stretch in the synovial joints, specifically, they they are sensory nerve endings within the joint capsules"
34
lamellar (Pacinian) corpuscles
these rapidly adapting stretch receptors are idal for measuring acceleration and rapid movement of the joints
35
bulbous corpuscles (Ruffini endings)
these slowly adapting stretch receptors are ideal for measuring the positions of nonmoving joints and the stretch of joints that undergo slow, sustained movements
36
free nerve endings (joints)
may be pain receptors
37
receptors resembling tendon organs
their function in joints is not known
38
cranial nerves
"12 pairs that attach to the brain and pass through various foramina in the skull; numbered from I through XII in a rostral to coudal direction; first two pairs attach to the forebrain, the rest to the brain stem
""Oh, Oh, Oh, To Touch And Feel Very Good Velvet, AH!"""
""Oh, Oh, Oh, To Touch And Feel Very Good Velvet, AH!"""
39
I. Olfactory
this is the sensory nerve of smell
40
II. Optic
because it develops as an outgrowth of the brain, this sensory nerve of vision is not a true nerve at all; it is more correctly called a brain tract
41
III. Oculomotor
"""eye mover"", this nerve innervates four of the extrinsic eye muscles--muscles that move the eyeball in the orbit"
42
IV. Trochlear
"""pulley"", this nerve innervates an extrinsic eye muscle that hooks through a pulley-shaped ligament in the orbit"
43
V. Trigeminal
"""threefold"", which refers to this nerve's three major branches; the nerve provides general sensory innervation to the face and motor innervation to the chewing muscles"
44
VI. Abducens
this nerve was so named because it innervates the muscle that abducts the eyeball (turns the eye laterally)
45
VII. Facial
this nerve innervates the muscles of facial expression as well as other structures
46
XIII. Vestibulocochlear
This sensory nerve of hearing and equilibrium was once called the auditory nerve
47
IX. Glossopharyngeal
"""tongue and pharynx"", structures that this nerve helps to innervate"
48
X. Vagus
"""vagabond"" or ""wanderer"", this nerve ""wanders"" beyond the head into the thorax and abdomen"
49
XI. Accessory
once called the spinal accessory nerve; originates from the cervical region of the spinal cord, enters the skull through the foramen magnum, and exits the skull with the vagus nerve; carries motor innervation to the trapezius and sternocleidomastoid muscles
50
XII. Hypoglossal
"""below the tongue"", this nerve runs inferior to the tongue and innervates the tongue muscles"
51
cranial sensory ganglia
lie along some cranial nerves (V, VII-X) just external to the bran; directly comparable to the dorsal root ganglie on teh spinal nerves
52
primarily or exclusively sensory nerves
(I, II, VIII) that contain special sensory fibers for smell (I), vision (II), and hearing and equilibrium (VIII)
53
primarily motor nerves
(III, IV, VI, XI, XII) that contain somatic motor fibers to skeletal muscles of the eye, neck, and tongue
54
mixed (motor and sensory) nerves
(V, VII, IX, X), these mixed nerves supply sensory innervation to the face (through general somatic sensory fibers) and to the mouth and viscera (general visceral sensory), including the taste buds for the sense of taste (specialy visceral sensory); these nerves also innervate pharyngeal arch muscles (somatic motor), such as the chewing mucles (V) and the muscles of facial expression (VII)
55
spinal nerves
thirty-one pairs, each containing thousands of nerve fibers, attach to the spinal cord; named accourding to their paint of issue from the vertebral column: 8 pairs of cervical nerves, 12 pairs of thoracic nerves, 5 pairs of lumbar nerves, 5 pairs of sacral nerves, 1 pair of coccygeal nerves (Co1)
56
rootlets
attach along the whole length of the corresponding spinal cord segment
57
dorsal root
contains the axonal processes of sensory neurons arising from cell bodies in the dorsal root ganglion
58
ventral root
contains the axonal processes of motor neurons whose cell bodies are located in the ventral gray column of the spinal cord
59
dorsal ramus/i
supply the dorsum of the neck and the back
60
ventral ramus/i
supply the anterior and lateral regions of the neck and trunk, and all regions of the limbs
61
intercostal nerves
supply the intercostal muscles, the skin of the anterior and lateral thorax, and most of the abdominal wall inferior to the rib cage
62
nerve plexus
network of nerves; the ventral rami of all spinal nerves except T2-T12 branch and join one another lateral to the vertebral column, forming __(es)
63
cervical plexus
buried deep in the neck, under the sternocleidomastoid muscle, and extends into the posterior triangle of the next; formed by the ventral rami of the first four cervical nerves; forms an irregular series of interconnecting loops from which branches arise
64
sutaneous nerves
(cutane=skin), carry sensory impulses from the skin (cervical plexus: skin of the neck, the back of the head, and the most superior part of the shoulder)
65
phrenic nerve
receives fibers from spinal nerves C3, C4, and C5, courses inferiorly through the thorax and innervates the diaphragm, providing somatic motor and sensory innervation to this most vital respiratory muscle
66
brachial plexus
lies partly in the neck and partly in the axilla (armpit) and gives rise to almost all of the nerves that supply the upper limb; formed by the wentral rami of cervical nerves C5-C8 and most of the ventral ramus of T1, may recive small contributions from C4 or T2
67
roots of the brachial plexus
ventral rami C5-T1, lie deep to the sternocleidomastoid; at the lateral border of this muscle, these rami unite to form the upper, middle, and lower trunks, each of which branches into and anterior and posterior division
68
lateral cord
anterior divisions from the upper and middle trunks give rise to the _
69
medial cord
anterior division from the lower trunk forms the _
70
posterior cord
composed of the posterior divisions of all three trunks (upper, middle, lower)
71
musculocutaneous nerve
main terminal branch of the lateral cord, courses within the anterior arm
72
median nerve
innervates most muscles of the anterior forearm and the lateral palm
73
ulnar nerve
branches off the medial cord of the brachial plexus, then descends along the medial side of the arm
74
axillary nerve
branch of the posterior cord, runs posterior to the surgical neck of the humerus and innervates the deltoid and teres minor muscles; its sensory fibers supply the capsule of the shoulder joint and the skin covering the inferior half of the deltoid muscle
75
radial nerve
a contiuation of the posterior cord, is the largest branch of the brachial plexus, innervating almost the entire posterior side of the uper limb, including all the limb extensor muscles
76
lumbar plexus
arises from the first four lumbar spinal nerves (L1-L4) and lies within the psoas major muscle in the posterior abdominal wall
77
femoral nerve
largest terminal branch of the lumbar plexus, runs deep to the inguinal ligament to enter the thigh
78
obturator nerve
passes through the large obturator foramen of the pelvis, enters the medial compartment of the thigh, and innervates the adductor muscle group, plus some skin on the supermedial thigh
79
sacral plexus
arises from spinal nerves L4-S4 and lies immediatle caudal to the lumbar plexus
80
sciatic nerve
thickest and longest nerve in the body, supplies all of the lower limb except the anterior and medial regions of the thigh (two nerves, tibial and common fibular nerves, wrapped in a common sheath)
81
tibial nerve
courses through the popliteal fossa and then descends through the calf deep to the soleus muscle
82
common fibular nerve
(perone=fibula) aka common peroneal nerve, supplies most structures on the anterolateral aspect of the leg
83
superficial fibular (peroneal) nerve
supplies the fibular muscles in the lateral compartment of the leg and most of the skin on the superior surface of the foot
84
deep fibular (peroneal) nerve
serves th muscles of the anterior compartment of the leg--the extensors that dorsiflex the foot
85
superior and inferior gletal nerves
innervate the gluteal muscles
86
pudendal nerve
"""shameful"" innervates the muscles and skin of the perineum, helps stimulate erection, and is responsible for voluntary inhibition of defecation and urination"
87
pudendal nerve block
injection needle is inserted just medial to the ischial tuberosity
88
"Hilton's law"
any nerve that innevates a muscles producing movement at a joint also innervates the joint itself (and the skin over it)
89
dermatome
"""skin segment"", the area of skin innervated by the cutaneous braches from a single spinal nerve"
90
shingles (herpes zoster)
varicella-zoster viral infection of sensory neurons innervating the skin; characterized by a rash of scaly, painful blisters usually confined to a narrow strip of skin on one side of the trunk, usually to one or several adjacent dermatomes
91
postherpetic neuralgia
a condition that occurs if the zoster virus damages the sensory nerve fibers and disrupts the sonsory pathways; sensory signals from the skin are exaggerated and even a light touch or a slight temperature change causes excruciating pain
92
migraine headachs
"extremely painful, episodic headaches that affect 1 billion people worldwide, relate to the sensory innervation of the brain's cerebral arteries by the trigeminal nerve: a signal from the brain stem causes the sensory nerve endings of the opthalmic division to release chemicals onto the ceral arteries that they innervate, signaling these arteries to dilate, which then compresses and irritates these sensory nerve endings causing the headache"
93
peripheral neuropathy
"refers to any pathologic condition of the peripheral nerves that disrupts nerve function; if an iddividual nerve is affected, it's a mononeuropathy, if multiple nerves are involved, it is a polyneuropothy; symptoms vary but include paresthesia, severe pain, burning, or loss of feeling; muscle weakness or paralysis"
94
ectodermal placodes
"""platelike"", plate-shaped thickenings of the head ectoderm, develop into some of the special senses sensory neurons"
95
pick up stimuli from inside and outside the body and then initiate impulses in sensory axons, which carry the impulse to the CNS
sensory receptors
96
bundles of peripheral axons
nerves
97
terminal boutons of motor neurons that innervate the effector organs, muscles, and glands
motor endings
98
structures that pick up sensory stimuli and then initiate signals in the sensory axons; most fit into two main categories: free nerve endings of sensory neurons and complete receptor cells
peripheral sensory receptors
99
sensitive to stimuli arising outside the body; most located at or near the body surface and include receptors for touch, pressure, pain, and temperature in the skin and most receptors of the special sense organs
exteroceptors
100
aka veseroceptors, receive stimuli from the internal viscera e.g. digestive tube, bladder, and lungs; different ones monitor a variety of stimuli, including changes in chemical concentration, taste stimuli, the stretching of tissues, and temperature; their activation causes us to feel visceral pain, nausea, hunger, orfullness
interoceptors
101
located in the musculoskeletal organs, e.g. skeletal muscles, tendons, joints, and ligaments; monitor the degree of stretch of these locomotory organs and send input on body movemeents to the CNS
proprieceptors
102
respond to mechanical forces such as touch, pressure, stretch, and vibrations
mechanoreceptors
103
mechanoreceptor that monitors blood pressure
baroreceptor
104
respond to temperature changes
thermoreceptors
105
respond to chemicals in solution (such as molecules tasted or smelled) and to changes in blood chemistry
chemoreceptors
106
in the eye respond to light
photoreceptors
107
(noci=harm), respond to harmful stimuli that result in pain
nociceptors
108
nerve endings of sensory neurons that monitor touch, pressure, vibration, stretch, pain, temperatur, and proprioception; two broad groups: free nerve endings and encapsulated nerve endings surrounded by a capsule of connective tissue
general sensory receptors
109
invade almost all tissues of the body but are particularly abundant in epithelia and in the connective tissue that underlies epithelia; primarily nociceptors and thermoreceptors; monitor the affective sense, those to which people have an emotional response
free nerve endings
110
aka Merkel discs, lie in the epidermis of the skin; each consists of a disc-shaped tactile epithelial cell innervated by a sensory nerve ending
epithelial tactile complexes
111
continue to respond and send out action potentials even after a long period of contiual stimulation
slowly adapting mechanoreceptors
112
free nerve endings that wrap around hair follicles, mechanoreceptors for light touch that monitor the bending of hairs (rapidly adapting)
hair follicle receptors
113
sensation disappears quickly even if the stimulus is maintained
rapidly adapting
114
consist of one or more end fibers of sensory neurons enclosed in a capsule of connective tissue
encapsulated nerve endings
115
"aka Meissner's corpuscle, a few spiraling nerve endings are surrounded by Schwann cells, which in turn are surrounded by an egg-shaped capsule of connective tissue; occur in the dermal papillae beneath the epidermis; rapidly adapting receptors for fine, discriminative touch; mainly occur in sensitive and hairless areas of the skin e.g. soles, palms, fingertips, nipples, lips"
tactile corpuscles
116
aka Pacinian corpuscles, scattered throughout the deep connective tissues of the body e.g. in the subcutaneous tissue deep to the skin; respond only to the initial application of pressure before they tire and stop firing (rapidly adapting receptors), best suited to moitory vibration; ~0.5-1mm wide and 1-2mm long
lamellar corpuscles
117
aka Ruffini endings, located in the dermis and elsewhere, contain an array of nerve endings enclosed in a thin, flattened capsule; adapt slowly and thus can monitory continuous pressure placed on the skin
bulbous corpuscles
118
virtually all are encapsulated nerve endings that monitor stretch in the locomotory organs; include muscle spindles, tendon organs, and joint kenesthetic receptors
proprioceptors
119
(neuromuscular spindles), measure the changing length of a muscle as that muscle contracts and is stretched back to its original length; an average muscle contains 50-100, which are embedded in the perimysium between tho fascicles
muscle spindles
120
(intra=within, fusal=the spindal), each spindle contains several modified skeletal muscle fibers surrounded by a connective tissue capsule
intrafusal muscle fibers
121
(extra=outside), the ordinary muscle cells outside the spindles, have more striations that the intrafusal muscle fibers
extrafusal muscle fibers
122
aka primary sensory endings, twirl around the noncontractile middle of the intrafusal fibers innervating the spindle center; these receptors are stimulated by the rate and degree of stretch of the muscle spindle
anulospiral endings
123
(secondary sensory endings), monitor the spindle ends (the only contractile parts of the spindle) and respond only to degree of stretch
flower spray endings
124
spinal motor neurons that cause the entire muscle (extrafusal fibers) to generate conractile force and resist further stretch
alpha efferent neurons
125
neurons preset the sensitivity of the spindle to stretch, most active when balance reflexes must be razor sharp
gamma efferent neurons
126
aka Golgi tendon organs, proprioceptors located near the muscle-tendon junction, where they monitor tension within tendons; each consists of an encapsulated bundle of tendon fibers (collagen fibers) whithin wihch sensory nerve endings are intertwined; relaxation reflex is important in motor activities that involve rapid alternation between flexion and extension
tendon organs
127
"""movement feeling"", proprioceptors that monitor stretch in the synovial joints, specifically, they they are sensory nerve endings within the joint capsules"
joint kinesthetic receptors
128
these rapidly adapting stretch receptors are idal for measuring acceleration and rapid movement of the joints
lamellar (Pacinian) corpuscles
129
these slowly adapting stretch receptors are ideal for measuring the positions of nonmoving joints and the stretch of joints that undergo slow, sustained movements
bulbous corpuscles (Ruffini endings)
130
may be pain receptors
free nerve endings (joints)
131
their function in joints is not known
receptors resembling tendon organs
132
"12 pairs that attach to the brain and pass through various foramina in the skull; numbered from I through XII in a rostral to coudal direction; first two pairs attach to the forebrain, the rest to the brain stem
""Oh, Oh, Oh, To Touch And Feel Very Good Velvet, AH!"""
""Oh, Oh, Oh, To Touch And Feel Very Good Velvet, AH!"""
cranial nerves
133
this is the sensory nerve of smell
I. Olfactory
134
because it develops as an outgrowth of the brain, this sensory nerve of vision is not a true nerve at all; it is more correctly called a brain tract
II. Optic
135
"""eye mover"", this nerve innervates four of the extrinsic eye muscles--muscles that move the eyeball in the orbit"
III. Oculomotor
136
"""pulley"", this nerve innervates an extrinsic eye muscle that hooks through a pulley-shaped ligament in the orbit"
IV. Trochlear
137
"""threefold"", which refers to this nerve's three major branches; the nerve provides general sensory innervation to the face and motor innervation to the chewing muscles"
V. Trigeminal
138
this nerve was so named because it innervates the muscle that abducts the eyeball (turns the eye laterally)
VI. Abducens
139
this nerve innervates the muscles of facial expression as well as other structures
VII. Facial
140
This sensory nerve of hearing and equilibrium was once called the auditory nerve
XIII. Vestibulocochlear
141
"""tongue and pharynx"", structures that this nerve helps to innervate"
IX. Glossopharyngeal
142
"""vagabond"" or ""wanderer"", this nerve ""wanders"" beyond the head into the thorax and abdomen"
X. Vagus
143
once called the spinal accessory nerve; originates from the cervical region of the spinal cord, enters the skull through the foramen magnum, and exits the skull with the vagus nerve; carries motor innervation to the trapezius and sternocleidomastoid muscles
XI. Accessory
144
"""below the tongue"", this nerve runs inferior to the tongue and innervates the tongue muscles"
XII. Hypoglossal
145
lie along some cranial nerves (V, VII-X) just external to the bran; directly comparable to the dorsal root ganglie on teh spinal nerves
cranial sensory ganglia
146
(I, II, VIII) that contain special sensory fibers for smell (I), vision (II), and hearing and equilibrium (VIII)
primarily or exclusively sensory nerves
147
(III, IV, VI, XI, XII) that contain somatic motor fibers to skeletal muscles of the eye, neck, and tongue
primarily motor nerves
148
(V, VII, IX, X), these mixed nerves supply sensory innervation to the face (through general somatic sensory fibers) and to the mouth and viscera (general visceral sensory), including the taste buds for the sense of taste (specialy visceral sensory); these nerves also innervate pharyngeal arch muscles (somatic motor), such as the chewing mucles (V) and the muscles of facial expression (VII)
mixed (motor and sensory) nerves
149
thirty-one pairs, each containing thousands of nerve fibers, attach to the spinal cord; named accourding to their paint of issue from the vertebral column: 8 pairs of cervical nerves, 12 pairs of thoracic nerves, 5 pairs of lumbar nerves, 5 pairs of sacral nerves, 1 pair of coccygeal nerves (Co1)
spinal nerves
150
attach along the whole length of the corresponding spinal cord segment
rootlets
151
contains the axonal processes of sensory neurons arising from cell bodies in the dorsal root ganglion
dorsal root
152
contains the axonal processes of motor neurons whose cell bodies are located in the ventral gray column of the spinal cord
ventral root
153
supply the dorsum of the neck and the back
dorsal ramus/i
154
supply the anterior and lateral regions of the neck and trunk, and all regions of the limbs
ventral ramus/i
155
supply the intercostal muscles, the skin of the anterior and lateral thorax, and most of the abdominal wall inferior to the rib cage
intercostal nerves
156
network of nerves; the ventral rami of all spinal nerves except T2-T12 branch and join one another lateral to the vertebral column, forming __(es)
nerve plexus
157
buried deep in the neck, under the sternocleidomastoid muscle, and extends into the posterior triangle of the next; formed by the ventral rami of the first four cervical nerves; forms an irregular series of interconnecting loops from which branches arise
cervical plexus
158
(cutane=skin), carry sensory impulses from the skin (cervical plexus: skin of the neck, the back of the head, and the most superior part of the shoulder)
sutaneous nerves
159
receives fibers from spinal nerves C3, C4, and C5, courses inferiorly through the thorax and innervates the diaphragm, providing somatic motor and sensory innervation to this most vital respiratory muscle
phrenic nerve
160
lies partly in the neck and partly in the axilla (armpit) and gives rise to almost all of the nerves that supply the upper limb; formed by the wentral rami of cervical nerves C5-C8 and most of the ventral ramus of T1, may recive small contributions from C4 or T2
brachial plexus
161
ventral rami C5-T1, lie deep to the sternocleidomastoid; at the lateral border of this muscle, these rami unite to form the upper, middle, and lower trunks, each of which branches into and anterior and posterior division
roots of the brachial plexus
162
anterior divisions from the upper and middle trunks give rise to the _
lateral cord
163
anterior division from the lower trunk forms the _
medial cord
164
composed of the posterior divisions of all three trunks (upper, middle, lower)
posterior cord
165
main terminal branch of the lateral cord, courses within the anterior arm
musculocutaneous nerve
166
innervates most muscles of the anterior forearm and the lateral palm
median nerve
167
branches off the medial cord of the brachial plexus, then descends along the medial side of the arm
ulnar nerve
168
branch of the posterior cord, runs posterior to the surgical neck of the humerus and innervates the deltoid and teres minor muscles; its sensory fibers supply the capsule of the shoulder joint and the skin covering the inferior half of the deltoid muscle
axillary nerve
169
a contiuation of the posterior cord, is the largest branch of the brachial plexus, innervating almost the entire posterior side of the uper limb, including all the limb extensor muscles
radial nerve
170
arises from the first four lumbar spinal nerves (L1-L4) and lies within the psoas major muscle in the posterior abdominal wall
lumbar plexus
171
largest terminal branch of the lumbar plexus, runs deep to the inguinal ligament to enter the thigh
femoral nerve
172
passes through the large obturator foramen of the pelvis, enters the medial compartment of the thigh, and innervates the adductor muscle group, plus some skin on the supermedial thigh
obturator nerve
173
arises from spinal nerves L4-S4 and lies immediatle caudal to the lumbar plexus
sacral plexus
174
thickest and longest nerve in the body, supplies all of the lower limb except the anterior and medial regions of the thigh (two nerves, tibial and common fibular nerves, wrapped in a common sheath)
sciatic nerve
175
courses through the popliteal fossa and then descends through the calf deep to the soleus muscle
tibial nerve
176
(perone=fibula) aka common peroneal nerve, supplies most structures on the anterolateral aspect of the leg
common fibular nerve
177
supplies the fibular muscles in the lateral compartment of the leg and most of the skin on the superior surface of the foot
superficial fibular (peroneal) nerve
178
serves the muscles of the anterior compartment of the leg--the extensors that dorsiflex the foot
deep fibular (peroneal) nerve
179
innervate the gluteal muscles
superior and inferior gletal nerves
180
"""shameful"" innervates the muscles and skin of the perineum, helps stimulate erection, and is responsible for voluntary inhibition of defecation and urination"
pudendal nerve
181
injection needle is inserted just medial to the ischial tuberosity
pudendal nerve block
182
any nerve that innevates a muscles producing movement at a joint also innervates the joint itself (and the skin over it)
"Hilton's law"
183
"""skin segment"", the area of skin innervated by the cutaneous braches from a single spinal nerve"
dermatome
184
varicella-zoster viral infection of sensory neurons innervating the skin; characterized by a rash of scaly, painful blisters usually confined to a narrow strip of skin on one side of the trunk, usually to one or several adjacent dermatomes
shingles (herpes zoster)
185
a condition that occurs if the zoster virus damages the sensory nerve fibers and disrupts the sonsory pathways; sensory signals from the skin are exaggerated and even a light touch or a slight temperature change causes excruciating pain
postherpetic neuralgia
186
"extremely painful, episodic headaches that affect 1 billion people worldwide, relate to the sensory innervation of the brain's cerebral arteries by the trigeminal nerve: a signal from the brain stem causes the sensory nerve endings of the opthalmic division to release chemicals onto the ceral arteries that they innervate, signaling these arteries to dilate, which then compresses and irritates these sensory nerve endings causing the headache"
migraine headachs
187
"refers to any pathologic condition of the peripheral nerves that disrupts nerve function; if an iddividual nerve is affected, it's a mononeuropathy, if multiple nerves are involved, it is a polyneuropothy; symptoms vary but include paresthesia, severe pain, burning, or loss of feeling; muscle weakness or paralysis"
peripheral neuropathy
188
"""platelike"", plate-shaped thickenings of the head ectoderm, develop into some of the special senses sensory neurons"
ectodermal placodes
