L14 head development Flashcards
where are the nasal placodes in 28-33d of develoment
on frontal prominence
what celluar/dev processes occur to shape strucutres that develop from nasal placodes
what strucutres are they
proliferation
cell migration
maxillary/mandibular/frontal prominence
what do nasal placodes devleop into
pits surrounded by medial and lateral nasal wellings
what do the lateral nasal sweeling develo into
nostril
what do the mandibular processes devleop into
the lower lip
how is upper lip formed
maxillary swelling grows
compresses medial nasal welling
then fuse
what day is the mammalian face recognisabel
47
when did NCC and skull ev
510mya
where cells form the head
ncc
paraxial mesoderm
endoderm
ectoderm
what cells and what process is the neurocranium/vault formed by
intramembraneous ossification within mesenchyme
NC and mesoderm
what cells and what process is the viseroanium/base formed by
intrambnous ossif
Endochondral ossif
NC +mesoderm
what cells and what process is the viscerocranium/facial bones formed by
ncc
intrambnous ossif
what is the differnece between endochondral ossif and intramembraneous ossif
eo - via a cartilage intermediate/slower
what is special abut face dev
from ncc
diff from axial skel
where ncc from and what process imp
developing n.tube migrate to head/neck primordia
EMT
what dictates the migration of ncc
tf
what tf do ncc that migrate to the head expr
neck expr
non-Hox homeodomain pr e.g. Otx
Hox expr
what is the differnece in differentiation between cranial ncc and trunk ncc
trunk can not develop into skeleton precursos eg chondrocytes and osteoblasts
both - melanocytes/neurons/glial/endocrine/connective
where do ncc arise from
at jucntion of neural plate and surface ectoderm
what specifices the postion of the ncc in rhomobomeres
hox code
where do the ncc in teh rhomobomeres migrate to
into mesenchyme of face and branchial arches
diff rhombo contribute diff ba (in segmental streams)
(r1-3=ba1)
what do the experiments transplant wrong rhomobomere into ba what show
if put r4 into ba1 get ectopic arch strucutre
ncc pre pattern
what evidence is there for plastcity in ncc cells
transplant allow to mix with neighbour cell change in gene expr seen
what strucuteres in neck and face do ncc contribute
face - mandibular and maxillary
neck - PA
