Lecture 3- Develop. Face, Nose, Ear, Eye Flashcards
(98 cards)
1
Q
What week does the nasal placode invaginate to form nasal pit, creating medial and lateral nasal processes; nasal pits deepen to form nasal cavity
A
Week 5-6
2
Q
A placode is a thickening of…
A
ectoderm
3
Q
Placodes thicken and then invaginate to form…
A
pits
4
Q
What week do the facial swelling fuse to create the rudiment of the face? The secondary palate is also formed this week
A
Week 7
5
Q
What week does the following happen:
- cranium expand
- 1st ossification centers
- ears move superiorly
- eyes move medially
- nose becomes more prominent
- facial proportions normalize as teeth are acquired
- paranasal sinuses
A
week 10
6
Q
During week 4, how many facial primordia develop as bulging prominences around the stomodeum?
A
5
7
Q
What is the stomodeum?
A
primitive mouth
8
Q
What are the 5 facial primorida called?
A
- frontonasal prominence (1)
- maxillary prominences (2)
- mandibular prominences (2)
9
Q
The frontonasal prominence is…. to stomodeum
A
rostral
10
Q
The maxillary prominence is… to stomodeum
A
lateral
11
Q
The mandibular prominence is … to stomodeum
A
caudal
12
Q
The mandibular prominence is nearly…. during the 4th week already
A
fused
13
Q
The…. membrane is only present the first couple of weeks of development
A
- buccopharyngeal (oropharyngeal)
* *NOT same as buccopharnyngeal fascia**
14
Q
The buccopharyngeal membrane separates the primitive oral cavity from the…. But it doesn’t stay, it ruptures and dissolves
A
oral pharynx
15
Q
Most facial structures develop during weeks
A
4-8 weeks
16
Q
The embryonic period goes until week…
A
8
17
Q
The fetal period begins in the … month
A
3rd
18
Q
In the fetal period, the cranium… which causes eyes to shift anteriorly and medially, the ears move… the nose becomes more…
A
- expands to accompany growing brain
- superiorly
- prominent
19
Q
In the fetal period, the facial skeleton appears small in comparison to rest of skull but proportions become normal once…
A
maxilla and mandible grow to allow space for teeth and once acquire paranasal sinuses
20
Q
At the end of the 4th week, the…. develop. These are 2 ectodermal thickenings that develop within frontonasal prominence
A
nasal placodes
21
Q
As the nasal placodes invaginate, mesenchyme surrounding the placodes proliferate forming elevations called:
A
medial nasal prominences (2)
and
lateral nasal prominences (2)
22
Q
Month2-3, maxillary prominences migrate medially, pushing… closer together and fuse in midline. The maxillary prominences never reach midline because midline is occupied by medial nasal prominences that fused
A
-medial nasal prominences
23
Q
Epithelium of nasal placodes sinks down into underlying mesenchyme to form……
A
nasal pits (future nostrils)
24
Q
Nasal pits also appear to sink in due to surrounding…
A
elevations (medial and lateral nasal prominences)
25
The nasal pits form the .... which will form the R. and L. nasal cavities
nasal sacs
26
The... separates nasal cavities from oral cavity and ruptures at end of week...
This creates a communication between nasal and oral cavities called...
- Oronasal membrane
- 6
- primordial choanae
27
The development of secondary palate establishes the... which separates nasal cavities from nasopharynx
choana
28
... gives rise to olfactory epithelium
neuroectoderm
29
The cleft between the lateral nasal prominences and the maxillary prominences is called..
nasolacrimal groove
30
The nasolacrimal is lost when... fuse with the maxillary prominences
lateral nasal prominences
31
The.... develops when ectoderm proliferates into underlying mesenchyme and forms a solid rod that separates from surface and canalizes
nasolacrimal duct
32
The superior end, of the nasolacrimal duct, dilates to form.... and the inferior end opens up into...
- nasolacrimal sac
| - inferior meatus of nasal cavity
33
The medial nasal prominences fuse and form....
intermaxillary segment
34
The intermaxillary segment includes.... (3)
1. philtrum of upper lip
2. premaxillary part of maxilla (4 incisors and associated gingiva)
3. Primary palate (only most anterior part of hard palate)
35
The secondary palate is the remainder of the hard palate and the...
soft palate (+ uvula)
36
During week 6: two plates of mesenchyme, called..., extends medially from the maxillary prominences
lateral palatine processes
37
The lateral palatine processes projecy inferomedially then swing upward to assume... and fuse with each other, with... and....
- horizontal position
- primary palate
- nasal septum
38
Clefts develop when the... cannot fuse because the tongue does not drop down like usual but instead gets in the way
lateral palatine processes
39
The secondary palate will be fused at... weeks
10
40
The... marks where the secondary palate fuses with primary palate and is used to indicate anterior and posterior palatal defects
incisive foramen
41
The developing secondary palate must fuse together as well as fuse with the... and ...
primary palate and nasal septum
42
The.... marks where lateral palatine processes fused together
median palatine raphe
43
The primary palate and anterior portion of secondary palate will ossify forming the bony...
hard palate
44
The posterior-most portion of the secondary palate does not ossify-- it extends posteriorly to form the ... and...
soft palate and uvula
45
Clefts can be of the ... or... or both. and can be bilateral or unilateral
- lip
| - palate
46
A cleft lip is an anterior palatal defect caused by failure of... to fuse with maxillary prominences on one or both sides
medial nasal prominences
47
Development of the ear: the... is first to develop at 4 weeks
inner
48
The inner ear develops as a bilateral thickening in surface ectoderm at the level of the caudal hindbrain and are called...
otic placodes
49
Ectoderm invaginates in each otic placode forming...
-otic pits
50
The edges of otic pits pinch off to form... that separate from surface ectoderm and will become the... for each ear
- otic vesicles
| - membranous labryinth
51
as inner ear develops, a diverticulum extends from otic vesicle to form the... and..
endolymphatic duct and sac
52
The otic vesicle is divided into 2 regions:
1. Utricular region
| 2. Saccular region
53
The Utricular region of the otic vesicle is located... and will become the... and ...
- dorsal
- utricle
- semicircular ducts
54
The Saccular region of the otic vesicle is located... and will become the... and ...
- ventral
- saccule
- cochlear ducts
55
As the cochlea duct develops, ... develop in the cartilage surrounding the cochlear duct and form the... space which has 2 divisions...
- vacuoles
- perilymphatic space
- scala vestbuli and scala tympani both filled with perilymph
56
The cartilage surround cochlear duct ossifies to form the bony labryinth encasing the... sturctures
inner ear
57
Cochlea development: Cells in walls of coiled duct form the...
spiral organ of Corti
58
Cochlea development: Cell bodies of CNVIII migrate along coils of cochlear duct and form the...
spiral ganglion
59
The external acoustic meatus develops from the... groove/cleft
1st
60
The tympanic membrane is formed from... and...
endoderm and ectoderm
61
The Malleus and Incus come from pharyngeal arch #? and are innervated by...
- 1
| - CNV
62
The Stapes comes from pharyngeal arch #? and is innervated by...
- 2
| - CNVII
63
External Ear: The Auricle (pinna) develops from ....
auricular hillocks
64
Auricular hillocks are mesenchymal proliferations surrounding the... pharyngeal groove
1st (mesenchyme from 1st and 2nd pharyngeal arches)
65
Auricles develop at level of... pharyngeal groove. Auricles will shift to final position (... level)
- 1st
| - eye
66
In the spiral organ of corti, there are hair cells that have a specific organization. These hair are organized in bundles that are associated with the ... membrane.
-tectorial
67
The vibration of the tectorial membrane (which is found within the cochlea duct) allows the hair bundles to move causing opening of ion channels that allows transduction of an electrical signal to produce a stimulus in the cochlear nerve whose cell bodies are in the ...
-spiral ganglion
68
The eye develops in week
5
69
The eye:
The middle layer is the... layer
The outermost layer is the... layer which is continuous with the cornea
- choroid
| - sclera
70
The optic groove (which will become vesicle next) is found in what portion of the developing brain?
prosencephalon/ forebrain
71
In the forebrain, during the development of the eyes, internally there is an... which started as an optic groove, and externally there is a...
- optic vesicle
| - lens placode
72
The optic vesicle will grow and will develop an... that allows it to stay connected to the forebrain
-optic stalk
73
The optic vesicle will become less round and fold into itself and will form an...
optic cup
74
Optic groove--> optic vesicle--> optic...
cups and stalks
75
The lens placode will thicken and invaginate forming a pit which will then form a... which is completely detached from the external surface
-vesicle
76
Retinal development: The outer layer of the optic cup will become the...
Retinal pigmented epithelium (non visual portion)
77
Retinal development: between the outer and inner layers of the retina there is a...
intraretinal space
78
Retinal development: The inner layer of the retina will become the....which is where the neurons of the retina will be
neural retina
79
As the retina develops, a space is left inferiorly to allow for blood vessels, this space is called...
retinal fissure
80
At about 10 weeks, the outer pigmented layer, intraretinal space and the inner neural layer of the retina will fused. Failure to fuse will cause a.... retina
detached
81
Rods and cones will be just adjacent to the.... layer of the retina
outer pigmented
82
The inner most layer of the neural retina will be the... layer
ganglion cell layer (group of cell bodies outside CNS)
83
... vessels provide blood in the developing eye through the retinal fissure
hyaloid
84
The hyaloid vessels are maintained in the optic nerve and it will become the
central artery and vein of the retina
85
The retinal fissure does not close until... no longer needs vascular supply.
lens
86
If the retinal fissure does not close off in the ... week as it should, a... results (congential defect)
- 7th
| - Coloboma
87
The ... is the artery in the optic nerve that comes from the opthalmic a. which comes from the ICA
central retinal artery
88
A coloboma is described as a.... appearance of the iris due to failure of the retinal fissure to close in the 7th week
key hole
89
The middle layer of the eye is called the... layer which is very well vascularized
choroid
90
The cornea has... layers
3 layers
91
The ciliary body contains the... and...
- ciliary muscle
| - ciliary processes
92
The ciliary body is composed from the
choroid and neural retinal components
93
The cells of the ciliary processes will produce... which is located....
- aqeuous humor
| - posterior and anterior to the iris
94
The retina in the iris is...
non visual (no photoreceptors)
95
The lens induces...
cornea
96
Cornea development:
outer layer derived from....
middle and inner layers derived from...
- ectoderm
| - mesenchyme (migrated neural crest)
97
The eyelids develop superiorly and inferiorly and fuse at around week .... and open in the ... week
- 8
| - 28th (7 months)
98
The eyelids are derived from...
mesenchyme (neural crest cells)
