Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy 2 > 3: Eye & Ear Development > Flashcards

3: Eye & Ear Development Flashcards

1
Q

when does the eye first appear

A

22 days

appears as optic grooves on sides of forebrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

steps to form optic cup and vesicle

A
  1. neural tube closes and grooves form the out-pocketings called OPTIC VESICLES
  2. vesicles contact surface ectoderm and LENS INDUCTION begins
  3. vesicle starts to invaginate and double-walled OPTIC CUP forms
  4. cells of surface ectoderm, in contact with optic vesicle, elongate and form LENS PLACODE
  5. placode develops into LENS VESICLE, which loses contact w/surface ectoderm and rests in mouth of optic cup
  6. layers of optic cup are initially separated by INTRARETINAL SPACE (which quickly disappears)
  7. inferior aspect of cup invaginates, forming CHOROID FISSURE allowing HYALOID A. to reach inner chamber of eye
  8. 7th week: edge of choroid fissure fuse and optic cup mouth becomes round opening –>future pupil
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

coloboma

A

key hole appearance of iris due to failure of retinal fissure to close in 7th week

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

eye at 7 weeks

A

outer layer of optic cup=retinal pigment layer

neural layer of retina is complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

pars optica retinae

A

posterior 4/5s of retina

rods and cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

mantle layer of retina

A

generates neurons & glia of outer and inner nuclear layers and ganglion layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

axons in retina

A

axons from neurons of deeper layers collect on retinal surface in a fiber layer

converge to form optic stalk and optic nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

iris & ciliary body

A

aka pars ceca retinae

anterior 1/5 of inner layer

divides into pars iridica retinae and pars ciliaris retinae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

pars iridica retinae

A

forms inner layer of iris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

pars ciliaris retinae

A

helps form ciliary body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

sphincter & dilator pupillae

A

region btwn optic cup and overlying surface epithelium

contains mesenchyme

forms sphincter & dilator pupillae mm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

ciliary muscle

A

formed by mesenchyme on outside of pars ciliaris retinae

controls lens curvature

connected to lens from inside, by elastic fiber network called suspensory ligament or zonula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

suspensory ligament

A

aka zonula

elastic fiber network that connects ciliary body to lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

lens

A

after lens vesicle forms, cells along posterior wall elongate anteriorly and form long fibers that fill lumen of vesicle

reach anterior wall of lend by 7th week

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

choroid

A

inner layer like pia

vascularized pigmented layer

emerges from loose mesenchyme that forms around eye in 5th week

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

sclera

A

outer layer like dura

continuous with dura of optic nerve

emerges from loose mesenchyme that forms around eye in 5th week

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

cornea formation

A

anterior chamber of mesenchyme, formed by vacuolization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

inner layer of cornea

A

in front of lens & iris

aka iridopupillary membrane (disappears)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

outer layer of cornea

A

substantia propria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

cornea contents

A

epithelial layer from surface ectoderm

substantial propria, aka stroma, continuous with sclera

epithelial layer that borders anterior chamber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

anterior & posterior chambers of cornea

A

filled w/fluid, aqueous humor, produced by ciliary body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

how do the anterior & posterior chambers of cornea communicate

A

thru pupil

fluid flows from posterior to anterior chamber, providing nutrients for avascular cornea & lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

where does fluid thru pass after anterior chamber

A

Canal of Schlemm at iridocorneal angle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what causes glaucoma

A

blockage of Canal of Schlemm

25
vitreous body
gelatinous material that fills interstitial space in the fine network of fibers btwn lens & retina
26
hyloid vessels
formed by mesenchyme surrounding eye primordium and invading optic eye via choroid fissure support lens in utero and form a vascular layer on inner retina
27
how is optic cup connected to brain
by optic stalk, with choroid fissure on ventral surface
28
what does the choroid fissure contain
hyaloid vessels
29
where do retinal nerve fibers going into the brain lie
along inner wall of the optic stalk
30
when does optic stalk become optic nerve
7th week, when choroid fissure closes hyaloid artery is now central artery of the retina
31
external ear function
collects sound
32
middle ear function
conducts sound
33
internal ear function
converts sound waves to nerve impulses & detects changes in equilibrium converting them into nerve impulses
34
internal ear development
22 days: otic placode thickening of surface ectoderm on each side of rhombencephalon otic placodes invaginate and form otic/auditory vesicles
35
otic vesicle development
ventral component: saccule and cochlear duct dorsal component: utricle, semicircular canals, endolymphatic duct
36
beginning of saccule & cochlea development
week 6 saccule forms tubular outpocketing aka cochlear duct cochlear duct penetrates mesenchyme while it spirals thru 2.5 turns
37
ductus reuniens
connection btwn cochlear duct and saccule
38
saccule, cochlea & Organ of Corti development (8-10 weeks)
1. mesenchyme around cochlear duct --> cartilage 2. cartilage becomes vacuolated; perilymphatic spaces arise (scala vestibuli & scala tympani) 3. vestibular membrane separates cochlear duct & scala vestibuli. basilar membrane separates cochlear duct & scala tympani 4. modiolus supports medial cochlear duct --> becomes axis of future bony cochlea
39
2 ridges of cochlear duct epithelial cells
inner ridge: future spiral limbus outer ridge: forms 1 row of inner and 3 rows of outer hair cells (sensory cells of auditory system)
40
tectorial membrane
gelatinous material attached to spiral limbus and rests on top of hair cells
41
what is the Organ of Corti made of
hair cells and tectorial membrane
42
where are impulses from Organ of Corti sent
to spiral ganglion and then to brain via CN VIII
43
when do semicircular canals appear
6th week as outpocketings of utricle
44
which end of the canals dilates
crus ampullare
45
which end of the canals does not dilate
crus nonampullare
46
crista ampullaris
crest formed by ampullae cells important for angular acceleration (equilibrium)
47
macule acusticae
develop in walls of utricle and saccule important for linear acceleration
48
where are impulses from cristae and maculae sent
to brain by CN VIII (body position)
49
tympanic cavity
endoderm from 1st pharyngeal pouch
50
tympanic cavity & auditory tube development
1st pharyngeal pouch expands distal aspect = tubotympanic recess --> primitive tympanic cavity proximal pouch = auditory (eustachian) tube
51
ossicles
incus & malleus=cartilage of 1st pharyngeal arch stapes=cartilage of 2nd pharyngeal arch
52
ossicles development
embedded in mesenchyme until 8th month, after which the endodermal lining connects them to the wall of the cavity via ligaments epithelial lining of primitive tympanic cavity extends into this new space
53
development of external auditory meatus
dorsal portion of 1st pharygeal cleft 1. cells at bottom of meatus proliferate and form MEATAL PLUG in 3rd month 2. in 7th month, plug dissolves and epithelium in floor of meatus contributes to eardrum formation sometimes plug persists and results in CONGENITAL DEAFNESS
54
eardrum consists of
ectodermal lining at bottom of meatus endodermal lining of tympanic cavity intermediate layer of connective tissue (fibrous striatum)
55
auricle development
from 6 mesenchymal proliferations at dorsal end of 1st and 2nd pharyngeal arches surrounding 1st cleft --formed from NEURAL CREST 3 hillocks on each side of meatus fuse and form auricle ear starts in LOWER NECK and ASCENDS as mandible develops top of ear should be at eye level, complications are common
56
anotia
absent external ear
57
microtia
small ear
58
preauricular appendages
accessory hillocks
59
preauricular pit
abnormal hillocks

Anatomy 2 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions