Special Senses Flashcards
(182 cards)
1
Q
Name general somatic senses
A
1) Touch
2) Proprioception
3) pain
4) temperature
2
Q
What do mechanosensors sense?
A
Touch and proprioception
3
Q
What is proprioception?
A
Body position
4
Q
What do nociceptors sense?
A
Pain
5
Q
What do thermoreceptors sense?
A
Temperature
6
Q
How many somatosensory pathways are there?
A
4
7
Q
Which neuron is closest to where a sensation is being felt?
A
1st order
8
Q
What does a sensory neuron convert stimuli into?
A
Action potential
9
Q
Where is cell body of 2nd order neuron located?
A
Spinal cord
10
Q
Where does second order neuron send signal?
A
Up spinal cord white matter directly to brain stem
11
Q
Where is the 3rd order neuron located?
A
Thalamus
12
Q
What is the sensory “train station depot” in the brain?
A
Thalamus
13
Q
Where is 4th order neuron located?
A
Somatosensory cortex
14
Q
Where is somatosensory cortex located?
A
Cerebral cortex
15
Q
What shaped neuron is the 1st order neuron?
A
Pseudo unipolar
16
Q
Where are dendrites of 1st order neuron?
A
In skin
17
Q
Where is cell body of 1st order neuron located?
A
Dorsal root ganglia
18
Q
What is the area of skin that a single neuron is responsible for called?
A
Receptive field
19
Q
What does a small receptive field yield?
A
High resolution (precision) sensitivity
20
Q
What areas have the smallest receptive fields in the body?
A
Fingers and tongue
21
Q
What is determined by frequency of nerve firing?
A
Stimulus strength
22
Q
What does high frequency of nerve firing yield?
A
Strong stimulus
23
Q
What is neuron frequency?
A
How many action potentials are fired in one minute
24
Q
What is a fast on, fast off firing receptor called?
A
Rapid or Fast Adapting
25
What is another term for fast adapting?
Phasic
26
What is a slow on and slow to turn off receptor?
Slow adapting
27
What is another term for slow adapting?
Tonic
28
Which order neuron is sensory adaptation specific to, typically?
1st order
29
3 somato sensory receptors?
1) Mechanoreceptors
2) Thermoreceptors
3) Nociceptors
30
Name 4 mechanoreceptors
1) Meissner Corpuscles
2) Merkel Discs
3) Ruffini Corpuscles
4) Pacinian Corpuscles
31
What 2 things do mechanoreceptors for touch sense?
1) Pressure
2) Deformation of skin
32
Where is Meissner corpuscle found?
Dermis
33
True or false: Meissner corpuscles are part of the connective tissue of dermis?
True
34
Which mechanosensor is NOT encapsulated?
Merkel discs
35
Where are a lot of Meissner corpuscles found?
Finger tips
36
What does Meissner Corpuscles sense?
Vertical indentations on the skin ex: Braille
37
Is the receptive field of the Meissner Corpuscle large or small?
Small
38
Are Meissner Corpuscles slow or fast adapting?
Fast
39
Where are Merkel discs?
Dermis
40
Do Merkel discs have a small or large receptive field?
Small
41
Are Merkel discs slow or fast adapting?
Slow
42
Where are Ruffini corpuscles?
Dermis and joints
43
What do Ruffini detect?
Stretching of skin and rotation of joints
44
Are Ruffini corp slow or fast adapting?
Slow
45
Does Ruffini have small or big receptive fields?
Big
46
Where are Pacinian corpuscles?
Deep dermis near SubCu
47
Do Pacinian corpuscles have big or small receptive fields?
Big
48
Are Pacinian fast or slow adapting?
Fast
49
What does Pacinian sense?
Vibration and movement
50
Name 3 proprioceptors of mechanoreceptors?
1) muscle spindle
2) golgi tendon organs
3) joint receptors
51
What do muscle spindles detect?
Muscle stretch
52
Where are muscle spindles found?
Perimysium (connective tissue)
53
Where is golgi tendon organ?
In tendon near muscle insertion on bone
54
What does Golgi tendon organ sense?
Tendon stretch and muscle force
55
What do joint receptors sense?
Stretch of joint capsule
56
What are thermoreceptors?
Sense temperature
57
Are thermoreceptors slow or fast adapting?
Slow
58
What is an ion channel that opens when temperature is sensed that triggers an action potential?
TRP Channel
59
What does TRP stand for?
Transient Receptor Potential
60
What temp activates a TRPV channel?
90-120F
61
What temp activates TRP-M8 channel?
50-104F
62
Where are TRP-V located?
Deep dermis
63
Where are TRP-M8?
Superficial dermis, close to epidermis
64
What senses temp below 50 or above 120?
Nociceptors (pain)
65
3 classes of nociceptors
1) thermal
2) mechanical
3) polymodal
66
True or false: pain threshold is the same for everyone?
True
67
True or false: pain tolerance varies person to person
True
68
How much of eye is visible on our body?
1/6
69
What are 3 layers of eye?
1) fibrous
2) vascular
3) neural
70
What are 2 parts of fibrous layer?
1) sclera
2) cornea
71
What part of the eye is tough, fibrous and anchoring?
Sclera
72
What runs through a small opening at the back of the sclera?
Optic nerve
73
What is the transition between the sclera and the cornea called?
Corneal limbus
74
What is the transparent, domed-shape portion of the eye?
Cornea
75
What is the cornea made of?
Stratified squamous epithelial cells
76
What is main function of cornea?
Helps to focus light on retina
77
What is the cornea considered “immune privileged”?
No blood vessels so no immune cells; makes transplant without rejection possible.
78
What is the vascular layer of the eye called?
Uvea
79
What are 4 parts of uvea?
1) iris
2) pupil
3) choroid
4) ciliary body
80
What are 2 muscles of the iris?
1) sphincter pupillae (circular)
2) dilator pupillae (radial)
81
What is the shape of the lens?
Biconvex
82
What does the lens do?
Focuses light on retina
83
What does ciliary body do?
1) connects to ligaments that hold and shape lens
2) makes fluid between cornea and iris
84
Where is choroid?
Behind retina
85
2 functions of choroid
1) provide nutrients via blood vessels
2) absorb light
86
What is the innermost layer of the eye?
Neural layer
87
Where are rods and cones?
Retina
88
What is responsible for night vision?
Rods
89
How many rods per eye?
120 million
90
What colors do cones “see”?
Red, green and blue
91
How many cones per eye?
6 million
92
Where are most cones located?
In the macula
93
What is the center part of the macula with highest concentration of cones?
Fovea
94
Where does optic nerve leave the retina?
Optic disc
95
Because the optic disc doesn’t have photo receptors, what is it known as?
Optic blind spot
96
What is contained in the anterior chamber of the eye?
Cornea and iris
97
Where is the posterior chamber of the eye?
Between iris and lens
98
What 2 chambers make up the anterior section of the eye?
Anterior and posterior
99
What fluid is in anterior section of the eye?
Aqueous humor
100
What fluid is in posterior section of the eye?
Vitreous humor
101
What produces aqueous humor?
Ciliary epithelium
102
What does aqueous humor do?
1) provide nutrients (lens, cornea)
2) structural support
103
Where does aqueous humor flow through out of the eye?
Trabecular mesh work (spongey)
104
What circular channel leads aqueous humor from trabecular mesh to aqueous vein?
Canal of Schlemm
105
What 2 functions is ear responsible for?
Hearing and balance
106
2 parts of outer ear
1) Pinna (auricle)
2) ear canal
107
Name 3 ear bones of middle ear
1) maleus
2) incus
3) stapes
108
Name 2 parts of inner ear
1) cochlea
2) semicircular canals
109
What does cochlea do?
Converts sound waves to electrical impulses
110
What do semicircular canals of inner ear do?
Help with balance
111
What is auricle (pinna) made of?
Cartilage
112
What is a lobule?
Ear lobe
113
What is the 1” tube that leads to the tympanic membrane?
External acoustic meatus (ear canal)
114
What produces wax in the ear?
Ceruminous glands
115
What is another name for tympanic membrane?
Ear drum
116
Where is middle ear located in skull?
Inside temporal bone
117
What forms the lateral wall of the middle ear?
Ear drum
118
What is the posterior wall of middle ear called?
Mastoid antrum
119
What is found in the anterior wall of middle ear that leads to nasopharynx?
Eustachian tube
120
Name 3 functions of eustachian tybe
1) equalizes pressure
2) protects ear from fluid reflux
3) clears mid ear secretions
121
Through what does vibration from stapes to inner ear travel?
Oval window
122
What are 2 parts of cochlea?
1) bony labyrinth
2) membranous labyrinth
123
What is bony labyrinth of cochlea filled with?
Perilymph
124
What is membranous labyrinth of cochlea filled with?
Endolymph
125
Is cochlea at the front or back of the head?
Front
126
What is cochlea responsible for?
Hearing
127
Where are semicircular canals found, front or back?
Back
128
What are semicircular canals for?
Balance
129
What connects the middle ear to the inner ear through the oval window?
Scala vestibula
130
What converts vibration to electrical impulse in the cochlea?
Organ of Corti
131
Where is Organ of Corti found?
Cochlear duct
132
What is considered the “mastermind of hearing”?
Organ of Corti
133
What are hearing receptors in Organ of Corti called?
Hair cells
134
What connects the middle ear to the inner ear through the round window?
Scala tympani
135
What CN receives electrical impulse?
CN 8
136
What are 2 parts of vestibular apparatus (inner ear)
1) semicircular canals
2) utricle and saccule
137
What contain fluid and balance receptors in their macula?
Utricle and Saccula
138
What is gustation?
Taste
139
What does the intrinsic muscle of the tongue do?
Helps tongue change shape
140
What does the extrinsic muscle of the tongue do?
Attaches and guides movement
141
What is the V-shaped groove across the rear of the tongue?
Sulcus terminalus
142
What does sulcus terminalus divide on the tongue?
Front 2/3 from back 1/3
143
What are bumps of lymphatic tissue on back of tongue?
Lingual papillae
144
What do lingual papillae do?
Fight pathogens with B & T cells
145
What give rough texture and helps food stick to tongue?
Anterior papillae
146
What is the most numerous type of papillae?
Filiform
147
What is the threadlike papillae that cover the anterior 2/3 of tongue?
Filiform
148
What are Filiform papillae for?
Touch (not taste)
149
Where are fungiform papillae found?
Tip if tongue
150
Where are foliate papillae found?
Sides of tongue
151
What are the large, round papillae found just in front of sulcus terminalis?
Circumvallate
152
What are the epithelial cells in taste buds?
Taste receptor cells
153
True/False: taste receptor cells can be found from the soft palate to the upper esophagus
True
154
How often are taste receptor cells replaced by basal layer of taste buds?
Every 2 weeks
155
Taste receptor cells are chemoreceptors that respond to what?
Tastants
156
What sticks out through taste pore on taste receptor and contacts tastants?
Gustatory hair
157
Cells bodies in the front of the tongue have axons that transfer taste to brain via which CN?
Facial nerve
158
Cells bodies in the back of the tongue and oral cavity have axons that transfer taste to brain via which CN?
Glossopharyngeal
159
Cells bodies in the back of throat and esophagus have axons that transfer taste to brain via which CN?
Vagus
160
What are 5 tastes?
Sweet
Salt
Sour
Bitter
Umami
161
What taste sweet/umami
Fungiform (tip of tongue)
162
What taste salt/sour?
Foliate (side)
163
What taste bitter?
Circumvallate (back)
164
How are salt/sour neurotransmitters released?
Depolarization
165
How are sweet/bitter/umami neurotransmitters released?
G-protein coupled pathway
166
4 factors that affect taste
1) hunger
2) adaptation
3) smell
4) age
167
What tastes are you more sensitive to when you’re hungry?
Sweet and salt
168
What is olfaction?
Smell
169
What 4 areas make up nasal cavity?
1) vestibule
2) respiratory region
3) olfactory region
4) lamina propria
170
What is the shell-like bony part of respiratory region called?
Conchae (superior, middle, inferior)
171
What does mucus in respiratory region do?
Trap pathogens
Moisten air
172
What is olfactory region lined with?
Olfactory epithelium
173
What does olfactory epithelium contain?
Olfactory receptor cells
174
What shaped cell supports olfactory receptor cells?
Columnar
175
What type of neurons do olfactory receptor cells have?
Bipolar
176
What does the cilia use to grab odorants?
G-protein receptors
177
How many different odors can we smell?
10,000+
178
How many different type of smell receptor proteins?
1000+
179
What are 2nd order neurons of olfactory bulb called?
Mitral cells
180
Which side of the olfactory tract is responsible for smell triggering emotion/memory?
Lateral
181
How quickly can adaptation of smell occur?
< 1 minute
182
What kind of cells are the gustatory hairs?
Epithelial
