Embryo Flashcards
Time period for head and neck to develop?
5-10 weeks
What is the ectoderm of the frontonasal prominence innervated by?
V1-GSA
What does the frontal nasal prominence form?
forehead, apex of nose
What does the medial nasal prominence form?
phithrum , nasal septum, medial upper lip
What does the intermaxillary segment form?
primary plate
What innervates the ectoderm of the maxillary prominence of arch 1?
V2-GSA
What innervates the ectoderm of the mandibular prominences ?
V3-GSA
Oblique facial cleft
failure of lateral nasal prominences and maxillary prominences to fuse
What are the mm of mastication innervated by?
the mesenchyme is innervated by SVE - V
arch I
What are the mimetric mm innervated by?
the mesenchyme innervated by SVE VII
Arch II- invade mandibular and maxillary swellings
What marks the boundary between the junction of primary and secondary palates and distinguishes anterior from posterior cleft deformation?
Incisive foramen
What causes an anterior cleft deformity ?
Cleft lip and anterior cleft palate
failure of medial nasal and maxillary swellings to fuse
(males)
What causes a posterior cleft deformity?
palatine shelves dont fuse
females
What causes a median cleft lip and bifid nose?
medial nasal prominences dont fuse - rare
The skeletal m of branchiomeric origin are innervated by what type of fibers?
SVE
What are the sensory fibers found in the branchial arches?
GSA - sensory for ectoderm
GVA - sensory for viscera (endoderm)
What does the 1st branchial arch form?
MM of mastication, ant. digastric, tensor tympani m, tensor palati m
incus and malleus
What is the innervation of arch 1?
trigeminal
What does the 1st groove form?
ectoderm: forms the external ear
- tympanic membrane and ext aud meatus
What mm and skeleton does the 2nd branchial arch form?
mimetic, stapedius mm
stapes and hyoid (lesser horn)
What is the innervation of arch II?
VII
What mm and skeleton forms from branchial arch 3?
stylopharyngeus m
hyoid (body, greater horn)
What is the innervation from arch 3?
IX
What artery forms from arch 3?
stem of internal carotids
What mm and skeleton forms from arch 4,6?
pharyngeal and laryngeal mm
laryngeal cartilages
What is the innervation of arch 4 and 6?
vagus
recurrent laryngeal n
What arteries form from arch 4 and 6?
aortic arch (L) subclavian (R)
What does the ectoderm of the brachial arches form? pouches or grooves?
grooves
What does the endoderm of the brachial arches form? pouches or grooves?
pouches
What is first arch syndrome?
treacher collins syndrome
impaired growth of midface
small chin, enlarged nose, cleft palate, and maybe cleft lip
in 50%: some conductive hearing loss due to underdevelopment of ossicles
What does the 1st pharyngeal pouch form?
inner and middle ear: eustachian tube and tympanic cavity
What does the 2nd brachial pouch form?
root of tongue, tonsil buds
What does the 3rd pharyngeal pouch form?
inferior parathyroid glands, thymus
What does the 4th pharyngeal pouch form?
superior parathyroid glands
How do thyroglossal ductal cysts form?
when thyroid descends in neck, thyroglossal duct connects the thyroid to the tongue and the foramen cecum
The diverticulum should solidify and thyroid lobes bud off
if the duct persist, cysts can form. remnants may include ectopic thyroid tissue. also some glandular often persists along midline as pyramidal lobes
What does the tongue develop from?
median mass of arch II (copula) and the hypobranchial eminence of arch III
What demarcates the anterior of the tongue from posterior?
sulcus terminalis
What innervates the intrinsic mm of the tongue?
GSE fibers from XII
What is the innervation of the ant 2/3 of the tongue?
VII - taste - SVA
V3 - sensory - GSA
Cranioschisis
failure of occipital and parietal bones to completely form or close
