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Flashcards in eye Deck (75)
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1
Q

where is the eye derived from

A

meso and ectoderm

2
Q

what is mesodermally derived

A

fibrous coats

3
Q

ectoderm creates

A

lens retina cornea and pigmented layers

4
Q

how many tunics

A

3

5
Q

name the 3 tunics

A

fibrous, vascular, and nervous/retina

6
Q

fibrious tunic is composed of

A

sclera and cornea

7
Q

what is sclera

A

white part of eye

8
Q

what is role of sclera

A
  • maintain shape if inside eye pressure increases

- tiny openings allow structures to pass through

9
Q

what structures pass through the eye

A

blood vessels

neurons

10
Q

what attaches to the sclera

A

extra ocular muscles

11
Q

anteriorly: what is sclera lined w/….what are the transitions between

A

conjunctiva, transition to cornea at limbus

12
Q

posteriorly: continuous w/ fibrous sheath that covers which cn

A

2

13
Q

what part of sclera is opaque

A

sclera

14
Q

what is the anterior part called

A

cornea

15
Q

describe cornea

A

clear, transparent

16
Q

primary role of cornea

A

refractory

17
Q

convex anterior or post

A

ant

18
Q

list the 5 layers of cornea from ant to post

A

corneal epithelium, anterior limiting lamina, substantia propria, posterior limiting lamina, endothelium

19
Q

what part is composed of the choroid, ciliariary body, and iris

A

vascular tunic

20
Q

choroid blood supply

A

rich

21
Q

where is choroid firmly attached to sclera

A

where the optic nerve penetrates it

22
Q

what is special about choroid and light

A

it is dark pigmented to limit the passage of light

23
Q

what is the ciliary body continuous with

A

choroid and iris

24
Q

what does the ciliary body produce

A

aqueous fluid and GAGs of vitrous body

25
Q

contraction of ciliary muscle allows lens to become ____ allow for ________ vision

A

convex; near

26
Q

what is the colored part of the eye

A

iris

27
Q

which part of eye has cooling effect

A

choroid : vascular tunic

28
Q

where is ciliary muscle located

A

ciliary body

29
Q

which two muscles are in the iris

A

sphicter pupillae and dilator pupillae

30
Q

what suspends the lens

A

ciliary body

31
Q

which iris muscle is regulated by para ; symp

A

sphincter pupillae; dilaror pupillae

32
Q

retina is the outgrowth of..

A

diencephelon

33
Q

what does retina contact internally, externally

A

vitreous body, choroid

34
Q

10 layers of retina: external to internal

A
pigmented layer
rods and cones
external limiting membrane
outer nuclear layer
outer plexiform layer
inner nuclear layer
inner plexiform layer
ganglion cell layer
nerve fiber layer
internal limiting membrane
35
Q

name 5 cells involved in vision pathway

A
photoreceptors
inner nuclear layer cells
ganglionic layer cells
lateral geniculate body
brodman area 17 of occipital lobe
36
Q

what structures are available on funduscopic exam

A

optic disc, macula lutea

37
Q

t/f optic disc contains no photoreceptors

A

t

38
Q

what is the darker area at the center of the fundus

A

macula lutea

39
Q

what is the middle of the maculae lutea

A

fovea centralis

40
Q

where does the optic nerve attach to the eyeball

A

optic disc

41
Q

what are the only photoreceptors in macula lutea

A

cones

42
Q

name the refractory components of the eyeball

A

cornea, aqueous humor, lens, vitreous body

43
Q

what is the most anterior refractory structure

A

cornea

44
Q

what is clear fluid secreted by ciliary process found on the post part of ciliary body

A

aqueous humor

45
Q

what is aqueous humor secreted into

A

posterior chamber

46
Q

describe path of aqueous humor

A

passes through pupil into anternior chamber, then laterally, leaving eyeball through scleral venous sinus

47
Q

what results from inc. pressure from anterior segment of eyeball

A

glaucoma

48
Q

describe of lens

A

transparent, biconvex, avascular

49
Q

t/f inc. concavity allows for near vision

A

f: convexity

50
Q

lens gets harder w/ age->more difficult ___ vision

A

presbyopia; near

51
Q

lens becomes less transparent

A

cataracts

52
Q

what fills posterior segment

A

vitreous body

53
Q

what connects optic n and post aspect of lens

A

hyaloid canal

54
Q

what seperates anterior segment from posterior segment

A

lens

55
Q

hyaloid canal is fxnal infetuses or adults

A

fetuses, contained fetal hyaloid artery

56
Q

accessory structures of the eye

A

extraocular muscles, lacrimal appararus, tarsal glands

57
Q

name parts of lacrimal appararus

A

lacrimal glands, lacrimal ducts, lacrimal sac, nasolacrimal duct

58
Q

what secretes tears

A

lacrimal glands

59
Q

what drains tears and to where

A

lacrimal ducts; lacrimal sac

60
Q

lacrimal sac is where

A

groove between lacrimal bone and maxilla

61
Q

nascolacrimal duct drains tears to

A

interior nasal meatus

62
Q

where are tarsal glands

A

located in each eyelid

63
Q

all arteries to eye are branches of

A

opthalmic artery

64
Q

what artery runs between sclera and cornea

A

long posterior ciliary artery, medial and lateral

65
Q

what is purpose of tarsal glands

A

reduce evaporation of tears through release of oily substance

66
Q

how many arteries form a ring around the optic nerve

A

6-12 short ciliary

67
Q

which arteries arch over/under eyeball

A

3-4 over 3-4 under

anterior ciliary arteries

68
Q

what does the central retinal artery travel w/

A

optic nerve

69
Q

name veins that drain the eye

A

anterior ciliary, long posterior ciliary, central retinal vein

70
Q

which branch of V supplies the eye

A

nasociliary of ophthalmic divison

71
Q

what is sensory for ciliary body, iris, and cornea

A

long ciliary nerves

72
Q

what is the only artery that supplies retina

A

central retinal artery

73
Q

what nerves are sensory for the eyeball

A

short ciliary nerves

74
Q

t/f post para fibers follow a similar path as symp and supply the ciliaris and dilator pupillae

A

f: sphincter pupillae

75
Q

post symp fibers from which plexus reach ciliaris and dilator pupillae

A

cavernous