Embryo T3 Flashcards
(141 cards)
1
Q
What mutant has specific behavioral defects related to the cerebellum?
Due to what abnormal cell?
Formation of what abnormal
A
Weaver
Radial glial cells in cerebellum
Formation of granular layer of the cerebellar cortex
2
Q
What is characterized by abnormal behavior and absence of normal cortical layering?
What is defective?
What does this do?
A
Reeler
Reelin: extracellular protein defective
Reelin: may serve as a stop signal for radial neuronal migration or as an insertional signal for migrating neurons
3
Q
A closure defect in spinal cord
A
Rachischisis
4
Q
Spinal cord and meninges remain in place but bony covering is incomplete
A
Spine bifida occulata
5
Q
Dura mater may be missing in the area of the defect and the arachnid layer bulge prominently beneath the skin. Spinal cord remains in place
A
Meningocele
6
Q
Spinal cord bulges or is entirely displaced into the protruding subarachnoid space
A
Myelomeningocele
7
Q
Major derivatives of diencephalon?
A
Epithalamus
Thalamus
Hypothalamus
8
Q
Rostral patterning center?
A
FGF-8
9
Q
What may serve as a stop signal for radial neuronal migration or as an insertional signal for migrating neurons
A
Reelin
10
Q
Dorsal patterning center?
A
BMPs and Wnts
11
Q
Ventral patterning center
A
Shh
12
Q
What is the major topographical change in the myelencpehalon?
A
Pronounced expansion of the roof plate to form the thin roof overlying the fourth ventricle
13
Q
Express of what genes is responsible for differentiation of nuclei in myelencephalon?
A
Hox genes
14
Q
Neural crest cells are from what?
A
Neural plate
15
Q
While in the neural tube neural crest cells are?
A
Epithelial
16
Q
What factors are involved in breaking free of the neural tube?
A
Snail-1, Snail-2, and Foxd3
17
Q
Neural crest cells form many components of the nervous system but do not form what?
A
Motor neurons
18
Q
Neural crest cells from trunk transplanted into head form most neural crest derivates except
-What also differentiates
A
Cartilage or skeletal elements (even though normally do)
Some cells differentiate into cholinergic parasym instead of adrenal sympathetic normally produced
19
Q
Pathway of cells in circumpharyngeal ridge
A
Migrate ventrally and then cranially to provide pathway for XII and related musculature
20
Q
Most neural crest cells from somites 1-3
A
Pass into pharyngeal arches 4 and 6 or form cardiac crest
21
Q
Neural crest cells from somites R4-R7
A
Make up vagal crest
Form parasympathetic innervation for digestive tract
22
Q
Vagal neural crest
- Associated with
- Para or Sym
- Factor
A
Gut enteric system
Parasympathetic
Mash-1
23
Q
What maintains the competence of neural cells to differentiate into autonomic neuron?
A
Mash-1
24
Q
What is involved in various pigment defects (white strip), deafness, cleft palate, ocular hypertelorism
- What crest(s)
- Mutation
A
Waardenburgs syndrome
Trunk and cranial
Pax3 mutations
25
What is characterized by coloboma, heart disease, atresia of nasal chonanae, retardation of development, genital hypoplasia in males, and anomalies of ear
-What crest(s)
CHARGE
Trunk and cranial
26
What is characterized by hypoplasia and reduced function of thymus, thyroid, and parathyroid glands and cardiovascular defects
- What crest(s)
- Mutation
DiGeorge Syndrome
Cranial
Deletion of Chr 22
27
What is a genetic disease manifested by multiple tumors of neural crest origin?
Neurofibromatosis
28
What is characterized by cafe au lait spots, peripheral nerve tumors, gigantism
Neurofibromatosis
29
Preplacodal region is induced by
Involves activation of
Involves inhibition of
Cranial mesoderm
Activation FGF
Inhibition of Wnt and BMP
30
In preplacodal region low concentration of BMP form
Placodes
31
In preplacodal region intermediate concentration of BMP form
Neural crest
32
In preplacodal region high concentration of BMP form
Neural plate
33
What induces formation of lens placed from lens ectoderm?
Optic vesicle
34
Absence of Pax6 in eye development
Optic vesicle can't induce formation of lens placode
35
What induces ectoderm to form neural plate
Chordamesoderm
36
What induces neural crest to form choroid, sclera?
Optic cup
37
What induces the formation of lens from lens vesicle?
Primitive retina and neural retina
38
Corneal epithelium is induced to from cornea by what?
Lens vesicle
39
Optic stalk is a lateral evagination of what?
diencephalon
40
groove in optic vesicle is what?
Choroid fissure
41
What runs in the choroid fissure?
Hyaloid artery to posterior chamber
42
What occurs in absence of Pax6
Early formation of optic vesicle but rest of eye doesn't form
Optic vesicle can't induce lens ectoderm
43
What inhibits expression of Pax 6
High concentrations of Shh
44
Low concentrations of Shh in distal optic stalk permits expression of Pax6 and development of what
Leads to formation of what
Optic vesicle
Retina
45
High concentrations of Shh in proximal optic stalk induces what
-Fxn
Expression of Pax2
| -Provide guidance of axons of ganglion cells from retina
46
What is necessary for corneal induction
Pax6
47
What is necessary for the differentiation of the pigmented retina
- Stimulated by what
Otx2
-Stimulated by Shh
48
What axis is fixed first?
| -Established by what gradients
Nasotemporal (anterior-posterior) axis
| -Gradients of Ephrins and receptors
49
What axis is fixed second?
| -Established by
Dorsoventral axis
| -Antagonistic actions of Shh and BMP along with ventropin, Tbx-5, Pax2, and Vax2
50
The absence of eye, lack formation of optic vesicle
| -Mutation
Anophthalmos
| -Rax
51
Small eyeball or vestigial eyeball
Microphthalamos
52
Nonclosure of the choroid tissue of the iris during the sixth or seventh week resulting in its persistence
Coloboma iridis
| Coloboma
53
Rathke's pouch is an evagination from the roof of what?
| What is its primordium for the anterior pituitary
Stomodeal ectoderm
| -Adenohypophysis
54
First arch develops into ______ because of the lack of _____ gene expression
Jaws
| Hox
55
Expression of what keeps arch 2 from differentiating into arch 1 and forming jaws
Hoxa2
56
Arch I nerve
CN V
57
Arch 2 nerve
CN VII
58
Arch 3 nerve
CN IX
59
Arch 4 nerve
CN X
60
Segmentation of cranial neural tube occurs as a result of what gene expression
Hox
61
What gives rise to neural crest tissue?
Neural tube
62
Pharyngeal arch derived musculature from
Mesoderm somitomeres
63
Pharyngeal arch mesenchyme (no muscles) from
neural crest
64
Frontonasal ectoderm is induced by ____ from what?
Shh from forebrain
65
Frontonasal ectodermal zone, shaping of tip of snout is done by what
Shh and FGF-8
66
Primordia for jaw
- arch
- 3 components
First arch
Maxillary processes
Mandibular processes
Meckel's cartilage
67
What part of Jaw primordial is from forebrain and midbrain
Maxillary processes
68
What part of jaw primordial is from midbrain and hindbrain
Mandibular processes
69
Meckel's cartilage is derived from
Arch 1
| Neural crest cells
70
What forms around meckel's cartilage
Mandible
71
Formation of temporomandibular joint involves early expression of what?
Barx-1
72
Quadrate bone of meckel's cartilage forms
Incus
73
Articular bone of meckel's cartilage forms
Malleus
74
Stapes is derived from what arch
Arch II
75
Primary palate
- Name
- Formed from
- Pair/unpaired
Premaxilla
Median palatine process
Unpaired
76
Secondary palate
- Formed from
- Pair/unpaired
lateral palatine processes
| Paired
77
What is necessary for tooth development to continue past the bud stage
Pax9
78
Primary enamel knots can give rise to secondary enamel knots which progress to what
Molar cusps
79
Salivary gland development depends on interactions between what
Epithelium and underlying mesenchyme
80
Branching pattern of salivary glands depends on what?
Shh
81
For salivary gland development the signaling between Shh and FGF occurs where
Within the epithelium
| Rather then between epithelium and mesenchyme
82
Lack of fusion of maxillary and nasomedial processes
Cleft lips
83
Incomplete or absent fusion of palatal shelves
Cleft palate
84
Malformation of anterior endoderm and prechordial plate leads to this clinical
Holoprosencephaly
85
Abnormal dentin
| Blue-grey or amber brown
Dentinogenesis imperfecta
86
Affect development of enamel
Amelogenesis imperfecta
87
Main organizer for pharyngeal arch development is
Foregut endoderm
88
Craniocaudal segmentation of pharyngeal arches is determined by
Hox genes
89
Pharyngeal arch formation depends on what?
FGF-8
90
First arch
```
Trigeminal nerve
Meckels cartilage
Lower jaw
Malleus
Quadrate --> incus
Rhombomeeres 1 and 2
Otx-2
```
91
Second arch
```
Hyoid
Facial nerve
Reichert cartilage
Lesser horn hyoid
Stapes
Styloid and stylohyoid
Muscles facial expression
Hoxa2
```
92
Third arch
```
Glossopharyngeal
Hyoid bone
Upper pharynx
Greater horn hyoid
Stylopharyngeus muscle
```
93
Fourth arch
Vagus
| Muscles and cartilage of larynx and lower pharynx
94
External auditory meatus
1st groove
95
First pouch
Tympanic cavity
| Auditory tube
96
Second pouch
Fossa palatine tonsils
97
Third pouch
Inferior parathyroid: shh
| Thymus: BMP-4
98
Fourth pouch
Superior parathyroids
99
Parafollicular C cells are from what pouch
| - secrete
Fourth pouch
| -Calcitonin
100
The opening of the thyroglossal duct that persists as a small pit at base of tongue
Foramen cecum
101
which kidney is nonfunctional
Pronephric kidney
102
Caudally to each mesonephric duct forms an evagination called
-Gives rise to
Ureteric bud or metanephric diverticulum
Ureter, renal pelvis, Collecting tubules
103
The metanephric tubules will not form in absence of what?
Mesonephric duct (and vice versa)
104
Prevents neurons from crossing the midline of the central nervous system
Slit-2 and Robo
105
Uroplakins
Proteins that make the ureter epithelium impermeable to water
106
Displayed in children with bilateral renal a genesis
| Flattened nose, wide inter pupillary space, receding chin, tapering fingers, low set ear
Potter sequence
107
Horseshoe kidney
Two kidneys fused at midline
108
Thousand of cyst within parenchymal kidney
Polycystic kidney disease
109
major defect in which the urinary bladder opens broadly onto the abdominal wall
Exstrophy of the bladder
110
Steps in potters syndrome
1. Renal agenesis -->
2. Reduced urinary output -->
3. Oligohydramnios-->
4a. Hip dislocation
4b. pulmonary hypoplasia --> death
4c. flattened face and ears
111
What is the first part of the reproductive system to develop
Gonads
112
The switch that determines whether the indifferent gonads develop into ovary to testis is
SRY on Y chromosome
113
Mesonephric tubules near the gonads will
- female
- male
anastomose w/ rete cords
- in female: rete cords will degenerate
- in males: tubules will be retained as part of closed duct system that convey sperm to exterior
114
In males the retained mesonephric tubules are called
Efferent ductules
115
If SRY gene then get what factor
Sox-9
116
Genital tubercle forms
Glans penis or clitoris
117
Genital folds
more medial paired genital fold will fuse in male to for
-Shaft of penis
remain unfused in female
-labia minora
118
Genital swellings
Fuse to form scrotum
| Unfused to form labia majora
119
What maintains meiotic competency of germ cells and without individuals would be sterile
Dazl
120
Primary heart field
- Name
- Part of heart
- Exposure
- Timeline
- Express
```
Heart crescent
Left ventricle and atria
-atria if high RA
-ventral if not RA
Most primitive
Express Hand-1
```
121
Secondary heart field
- Part of heart
- Derived
- Form
- Express
Right ventricle and proximal outflow tract
Derived from pharyngeal mesoderm
Can form cardiac or skeletal muscle
Express Hand-2
122
What do interstitial cells and vasculature smooth muscle form from
Proepicardium --> epicaridum
123
Primary myocardium is guided by
Tbx-2
124
What is the first asymmetrical embryonic structure to appear
Cardiac tube
125
Chamber myocardium is guided by
Tbx-5
126
Broader proximal part of bulbus cordis
Conus arteriosus
127
Narrow distal part of bulbs cordis
Truncus arteriosus
128
Interatrial septum primum
Downward growth from cephalic wall of single atrium to endocardial cushion
Separates atrium into left and right chambers
129
Interatrial septum secundum
Forms to the right of septum primumand grows from dorsal to the ventral part of atrium
130
Interatrail foramen primum
right to left atrial shunt
131
Interatrail foramen secundum
continues right to left shunt after the foramen primum closes with fusion of the septum primum with the endocardial cushion
132
Foramen ovale
- what is it
- where
Right to left atrial shunt
| Space formed within the septum secundum
133
Third pair aortic arches
Internal carotids
134
First and second aortic arches
Degenerate
135
common carotids are derived from
ventral aorta between 3rd and 4th aortic arches
136
Fourth aortic arch
- Right
- Left
Right- Right subclavian A
Left- Aortic arch
137
Fifth aortic arch
Degenerates
138
Sixth aortic arch
- associated with
- dorsal portion
Pulmonary system
Dorsal portion becomes ductus arterioles shunt --> ligamentum arteriosus
139
Right vitelline vein becomes
Portal vein
140
Left umbilical vein becomes
Hepatic portal vein
141
What allows oxygenated placental blood to bypass capillary network of liver
Ductus venosus
