Special Senses Flashcards
1
Q
What type of receptor arespecial senses
A
Complex
Sense organs
2
Q
How much of eye surface is external
A
Only one sixth
3
Q
List the accessory eye structures
A
Eyebrows Eyelids Conjunctiva Lacrimal apparatus Extrinsic eye muscles
4
Q
Where are eyebrows
A
Above supraorbital margins
5
Q
What are functions of eyebrows
A
Shade eye
Prevent sweat from reaching eye
6
Q
What depresses eyebrow
A
Contraction of obicularis oculi
7
Q
What is another term for eyelid
A
Palpebrae
8
Q
What are canthi
A
Medial and lateral angles of eyelids
Called commisures
9
Q
What are tarsal plates
A
Connective tissue that support eyelids internally
10
Q
What muscle closes the eye
A
Obicularis oculi
11
Q
What muscle gives eyelid motility
A
Levator palpebrae superioris
12
Q
What initiates the blink reflex
A
Eyelashes
13
Q
What are tarsal meibomian glands
A
Secrete oil to lubricate eyelid
On eyelid edge
14
Q
Describe lacrimal caruncles
A
Mass of soft tissue with glands that produce white oily secretion
15
Q
Describe ciliary glands
A
Sebaceous glands in eyelash follicles
16
Q
What does bulbar conjunctiva cover
A
Only the whites of eye
Not the cornea
17
Q
Describe the conjunctiva
A
Transparent mucous membrane that lines eyelids and eye
Palpebral conjunctiva
Bulbar conjunctiva
18
Q
What do tears contain
A
Mucus
Antibodies
Lysozyme
19
Q
Describe the route tears take
A
Produced in lacrimal glands
Enter eye via superolateral excretory ducts
Exit eye by lacrimal punctum
Drain into nasolacrimal duct
20
Q
Where do the 4 rectus eye muscle originate from
A
Annular ring
21
Q
Where do they oblique eye muscles move the eye to
A
Into vertical plane
22
Q
What nerve controls lateral rectus
A
Abducens
23
Q
What nerve controls superior oblique
A
Trochlear
24
Q
What are the 3 layer of the wall of eye
A
Fibrous
Vascular
Sensory
25
What separates the interior cavity into segments
The lens
26
What is the fibrous layer composed of
Opaque sclera
| Cornea
27
What is role of sclera
Protect the eye
| Anchor to muscles
28
What make up the vascular layer
Choroid
Ciliary body
Iris
29
What does choroid region do
Prevent light from scattering
| Supply blood to eye tubics
30
What does choroid form
Posterior portion of uvea
31
What is ciliary body made of
Smooth muscle bundles
32
What is the role of the ciliary body
To anchor suspensory ligaments to hold lens
33
What are the 2 portions of the iris
Sphincter pupillae
| Dilator pupillae
34
What does the iris do
Regulate amount of light entering eye by changing pupil size
35
Describe the sensory layer
The retina
| Made of two layers
36
What are the 2 retina layers
Pigmented layer
Prevents light scattering
Inner neural layer
37
What is in the neural layer of retina
Photoreceptors
Bipolar cells
Ganglion cells
38
What do axons of ganglion cells do
Form the optic nerve
39
Where do the ganglion axons run
Along inner surface of retina
| Leave eye as optic nerve
40
Describe the optic disk
Blind spot
No photoreceptors
Where optic nerve leaves eye
41
Where are cones found
In macula lutea
| Concentrated at fovea centralis
42
Basic info about rods
Don't see color
Highly sensitive
For dim light
Peripheral vision receptors
43
Basic info about cones
See in color
Sharp image
Require bright light
44
Where are rods located
Around periphery retina
45
What are the two blood sources of te neural retina
Outer from choroid
| Inner from central artery and vein
46
How can you see the vessels in the eye
With a ophthalmoscope
| Radiate from optic disk
47
What is posterior segment filled with
Vitreous humor
48
What is anterior segment filled with
Aqueous humor
49
What is function of vitreous humor
Transmit light
Support lens
Hold neural retina against pigmented layer
Contribute to intraocular pressure
50
What is anterior segment divided into
Two chambers
Anterior from cornea to lris
Porterior from iris to lens
51
What is function of aqueous humor
Support
Nourish
Remove waste
52
What is aqueous humor like
Plasma
53
Where does aqueous humor go
Drains to scleral venous sinus
| Via the canal of schlemm
54
What happens if aqueous humor can't drain
Pressure builds up
Optic nerve is damaged
Causes glaucoma
55
What does lens allow
Precise focusing of light on retina
56
What is lens made of
Epithelium differentiate into fibers
| Lens fiber
57
Describe lens fibers
Cells filled with transparent proteins
| Called crystalins
58
What is a cataract
A cloudy lens
59
Where is visible light spectrum
Between UV and infrared
60
What responds to different light wave lengths of visible spectrum
```
Different cone types
3 kinds
Blue
Green
Red
```
61
What happens as light passes through. Convex lens
Bends to converge at focal point
| Image is upside down and reverse
62
What 3 places do light refraction occur in eye
Cornea
Entering lens
Leaving lens
63
Describe far point f vision
Beyond point lens does t need to change shape to focus
64
What three things does close vision require
Accommodation
Construction
Convergence
65
Describe accommodation
Changing lens shape by ciliary muscle to increase refractory power
66
Describe constriction
Pupillary reflex constricts pupils to prevent scattered light rays from entering eye
67
Describe convergence
Medial rotation of eye toward object
68
What is an emmetropic eye
Normal eye
| Light focused
69
What is another term for nearsighted
Myopic eye
70
What is another term for farsighted
Hyperopic eye
71
Describe myopic eye
Too long
| Focal point in front of reriba
72
Describe Hyperopic eye
Too short
| Focal point is behind retina
73
How do you correct myopic
Concave lense
| Radial keratotomy
74
How do you correct Hyperopic
Convex lense
75
What is photo transduction
Process of light energy into graded potential
76
What do both Rods and cones contain
Photopigments
In stacks of disclike plasma membrane folds
Change shape as they absorb light
77
What wavelengths of light to rods absorb
All wavelengths of visible light
78
How does input from rod reach ganglion cell
Converging circuit
| Fuzzy images
79
How does visual input reach ganglion from cone
One cone synapse with one ganglion
Higher resolution
Colir
80
What is retinal
A light absorbing molecule
81
How does retinal work
Combines with opsin proteins to form visual pigments
| Isomerization initiates electrical impulses in optic nerve
82
What are the 2 shapes of retinal
Bound to opsin 11 cis
| When activated by light all trans
83
What is the visual pigment in Rods
Rhodopsin
84
How is rhodopsin formed
11 cis retinal combined with opsin
85
What occurs when rhodopsin absorbs light
Retinal changes shape to all trans isomer
Retinal and opsin separate
Pigment is bleached
Opsin activated
86
What is retinal made from and similar to
Vitamin A
87
How many types of visual pigments are there
4 types
88
How is rhodopsin regenerated
All trans retinal to 11 cis using ATP
| 11 cis and opsin recombine to form rhodopsin
89
What occurs during light phase
Pigment bleached
| Rhodopsin break down
90
What happens during dark phase
All trans converted back to 11 cis
| Rhodopsin regenerated
91
How are colors perceived
Activation of multiple cones
92
How are cones activated
Similar to rods
More energy required
Same visual pigments
93
What causes color blindness
Lacking one cone type
X linked
Common to be missing red or green
94
What occurs in the dark
Ca and Na channels open
Depolarized to -40
Glutamate is released to bipolar cell
Bipolar cells are hyperpolarized and don't release anything to ganglion
95
What occurs in the light
```
Light splits rhodopsin
Opsin activated
Channels close
Membrane hyperpolarized
No neurotransmitters released
Bipolar cells depolarize
Depolarize ganglion
```
96
What happens when all rhodopsin is bleached
In high light Rods can't function
Don't receive anymore stimuli
Cones still respond
97
Adaption from light to dark
Both rods and cones don't work
Cones don't have enough light
Ross already bleached
Retinal sensitivity restored as rods accumulate rhodopsin
98
Adaption from dark to light
Both Rods and cones dazzled
Rod function is lost all are bleached
Cones activated
99
What forms optic nerve
Retinal ganglion
100
What decussates at optic chaisma
Medial optic nerve fibers
101
Where do fibers go after chiasm
The thalamus
102
Where do optic fibers go after thalamus
Visual cortex via internal capsule
| For conscious perception
103
Where do fibers for visual reflexes end
Superior colliculi
104
What does melanopsin do
Respond to light independent of vision
Mediates pupillary light reflexes
Sets biorhythm via hypothalamus
105
What causes three dimensional vision
Cortical fusion of different images
| Depth perception lost when only using one eye
106
Description of thalamic visual processing
```
Lateral geniculate nuclei info on:
Movement
Segregate retinal axons for depth perception
Emphasis on high cone region
Sharpen contrast
```
107
What is the primary visual cortex called
Striate cortex
| Fibers from leteral geniculate nuclei
108
What are visual association areas called
Prestriate cortices
Form
Color
Motion
109
What are the chemical senses
Gustatory
| Olfactory
110
What do chemireceptors respond to
Chemical in solution
Saliva
Nasal fluid
111
What is organ of smell
Olfactory epithelium
| On roof of nasal cavity
112
What are olfactory receptor cells like
Bipolar neurons with cilia
113
What happens when olfactory receptors have ligand bound
Proteins initiate g protein camp second messenger system
Camp opens channels
Depolarization of receptor causes action potential
114
Why do olfactory receptors adapt
Ca channels allow it
| Decrease response
115
Where do olfactory receptors synapse
In gonerular with mitral cells
116
What do gomerular mitral cells produce
Process odor signals before sending to olfactory cortex via thalamus
Or to hypothalamus
117
What are the types of tongue papillae
Filliform
Fubgiform
Curcumvallate
118
What do filliform do
Give tongue roughness
119
What do fungiform do
Give tongue redish color
| Contain taste buds
120
What do circumvallate do
Form v
| Contain taste buds
121
What are cell types in taste buds
Insulating cells
Basal cells stem
Taste cells
122
What causes sour taste
Hydrogen ions
123
What causes bitter taste
Alkaloids
| Glucosinolates
124
What causes umami taste
Amino acid glutamate
125
What causes salt taste
Metal ions
126
What mut happen for something to be tasted
```
Dissolve in saliva
Contact gustatory hairs
Depolarize taste cell
Release neurotransmitter
Graded potential to AP
```
127
What converts Taste energy to nerve impulse
```
Increased intracellular Ca
Ca released for bitter
Na
H
Closure of K for sweet
```
128
What nerves carry impulses of taste to medulla
7 and 9
| Facial and glosso
129
What receptors influence taste
Chemo
Thermo
Mechano
Nocic
130
What is tympanic membrane made of
Connective tissue
131
What is bony labyrinth fille with
Perilymph
132
What is membranous labyrinth filled with
Endolymph
133
What inside vestibule
Static equilibrium of maculae
134
What is housed in ampulla
Dynamic equilibrium receptors of crista ampullaris
135
What does oval window move
Perilymph in scala vestibuli
136
What stimulates cochlear nerve
Moving hair cells
137
Where do high frequencies short cut through
Cochlear duct
| Buldges round window
138
Where do inadible sounds travel
Around the helicotrema
139
What does exciting cilia in organ of corti cause
Mechanical gates open
Graded potential
Impulses to brain
140
Where are hairs of organ of corti
Into endolymph
| Touch the tectorial membrane
141
What is auditory pathway to brain
```
Cochlea to spiral ganglion
To cochlear nuclei
Then to olivary nucleus
Inferior colliculi
Then to auditory cortex
```
