exam 3 eye sight Flashcards
(89 cards)
1
Q
what sense is dominant
A
sight
2
Q
_____ than half of the body’s sensory receptors related to vision
A
more
3
Q
visual processing by ______ ______ ______
A
half cerebral cortex
4
Q
the eye is ____ connected by bone
A
not
5
Q
visual receptors are found in the ____
A
eye
6
Q
what are the four accessory organs for sense of sight
A
-eyelids
-eyelashes
-lacrimal glands
-extrinsic eye muscles
7
Q
what are the four layers the compose the eyelids
A
-skin
-muscle
-connective tissue
-conjunctiva
8
Q
what muscle closes the eyelid
A
the Orbicularis oculi
9
Q
what muscle opens the eyelid
A
levator palpebrae superioris
10
Q
What prevents contacts from slipping to brain
A
conjunctiva
11
Q
transparent mucous membrane
A
conjunctiva
12
Q
conjunctiva produces a _____ ______ secretion
A
lubricating mucous
13
Q
What keeps the eye from drying out
A
the conjunctiva
14
Q
The conjunctiva is rich is ______ _____
A
blood vessels
15
Q
what structures make up the lacrimal apparatus
A
-lacrimal gland
-canaliculi
- lacrimal sac
- nasolacrimal duct
-lysozyme
16
Q
in orbit lateral to eye
-secretes tears
A
Lacrimal gland
17
Q
2 ducts that collect tears
A
canaliculi
18
Q
-collects tear from canaliculi
-lies in groove in lacrimal bone
A
lacrimal sac
19
Q
-collects from lacrimal sac
-empties tears into nasal cavity
A
nasolacrimal duct
20
Q
antibacterial component of tears
A
lysozyme
21
Q
what eye muscle rotates eye up and medially
A
superior rectus
22
Q
what eye muscles rotates eye adown and medially
A
inferior rectus
23
Q
what eye muscles rotates ye medially
A
medial rectus
24
Q
what eye muscle rotates eye laterally
A
lateral rectus
25
what eye muscle rotates the eye down and laterally
superior oblique
26
what eye muscle rotates the eye up and laterally
inferior oblique
27
what cranial nerve helps the function of directing eyeball movement, constricting iris, raising eyelid
Cranial nerve III
28
cranial nerve III fibers extend from ______ through superior orbital fissures to ____ of six extrinsic eye muscles
midbrain
-4
29
what is the primary motor nerve that directs eyeball (superior Oblique)
The trochlear nerve (IV)
30
trochlear nerve fibers from ____ _____ enter orbits via ______ _______ fissures to innervate superior _______ muscle
-dorsal midbrain
-superior orbital
-oblique
31
Primary motor innervating lateral rectus muscle
the abducens nerves
32
what are the three layers for the wall of the eye
-outer (fibrous) tunic
-Middle (vascular) tunic
-Inner (nervous) tunic
33
the outer (fibrous) tunic includes:
cornea and sclera
34
-anterior
-transparent
-bends light
-highest refracting power
cornea
35
-posterior
-white opaque
-protects eye , attaches muscle
sclera
36
this part of the fibrous layer has an amazing rate of repair and no blood vessels
cornea
37
the _____has many pain receptors that contribute to _____ and _______ reflexes
-cornea
-blinking
-tearing
38
this part of the fibrous layer protects and shapes the eyeball it also anchors extrinsic eye muscles
sclera
39
the _____ is continuous with dura mater of brain posteriorly
sclera
40
what structures does the middle (vascular) tunic include
-choroid coat
-ciliary body
-iris
41
what structure of the middle (vascular) tunic is the posterior five-sixths and provides blood supply
choroid coat
42
the choroid coat contains ______ and _______
melanocytes and melanin
43
what is the point of melanin in the choroid coat
it helps prevent light scattering
44
what structure of the middle (vascular) tunic is part of the anterior portion and is the thickest portion/ pigmented
ciliary body
45
the _____ forms rings to hold lens and changed lens shape for focusing
ciliary body
46
what structure of the middle (vascular) tunic is anterior to the ciliary body and is in front of the lens
Iris
47
the ______ is pigmented and controls light entering eye
iris
48
the _____ cavity of eye is between the ______ and ______
anterior
-cornea
-lens
49
the anterior cavity is filled with a water fluid called ______ ______
aqueous humor
50
this structure of the anterior portion of the eye is transparent, behind iris, held in place by suspensory ligaments of ciliary body , ad focuses light rays
lens
51
the lens changes ____ to precisely focus light on ______
-shape
-retina
52
the lens is flexible and ______
avascular
53
what are the two regions of the lens
-lens epithelium
-lens fibers
54
Lens ______ form bulk of lens
fibers
55
_______ adds new fibers continuously
epithelium
56
the lens fibers are filled with a transparent protein called _______
crystallin
57
Les becomes more ______ and ____ elastic with age
-dense
-less
58
What causes the lens to become more elastic and less dense with age
cataracts
59
what starts to clump when someone has cataracts
crystallin proteins
60
what is an accommodation
a change in the shape of the lens to view close objects
61
lens thickens and becomes more convex when focusing on a _______object
62
lens things and becomes flatter when focusing on a ________ object
distant
63
what controls the amount of light entering the eye
the iris
64
the iris consists of ______ tissue and ______ muscle
-connective
-smooth
65
______ is a window or opening in center of iris
pupil
66
____ light stimulates _____ muscles and the pupil dilates
-dim
-radial
67
____ light stimulates ______ muscles and the pupil constricts
-bright
-circular
68
if the sphincter pupillae muscle contracts then the pupil
decreases
69
if the dilator pupillae muscle contracts the pupil ...
increases
70
What are the two muscles of the iris
-sphincter pupillae
-dilator pupillae
71
the lens and ciliary body separate into two segments what are they called
anterior and posterior segments
72
the anterior segment of the lens is composed of two chambers what are they called
anterior and posterior chamber
73
the anterior chamber of the anterior segment is between the ___ and ______
cornea and iris
74
the posterior chamber of the anterior segment is between _____ and _______
iris and lens
75
the anterior segment contains ______ humor
aqueous
76
the ______ humor is continuously formed by ______ of ciliary body
-aqueous
-capillary
77
aqueous humor drains via canal of _______ at sclera-cornea junction
schlemm
78
Supplies nutrients and oxygen mainly to lens and cornea but also to retina, and removes wastes
aqueous humor
79
space enclosed by lens ciliary body and retina
posterior cavity
80
the posterior cavity contains ______ humor
vitreous
81
the ______ humor is a thick gel that supports internal structures and maintains shape of eye
vitreous
82
the inner (nervous) tunic consists of ____
retina
83
the retina contains visual receptors called ....
photoreceptors
84
the retina is ________ with optic _____ in the back of they eye
-continuous
-nerve
85
the retina is composed of three different layers called:
-macula lutea
-fovea centralis
-optic disc
86
what is the spot in retina called
macula lutea
87
what is the center of the macula lutea that produces sharpest vision called
fovea centralis
88
what is the blind spot that contains no visual receptors and is found where nerve fibers from retina leave the eye to become optic nerve
Optic disc
89
