Pharyngeal Arches Flashcards
Pharyngeal arches appear ? weeks as ??? migrate into the head and neck region
in 4th and 5th
neural crest cells
Maxilla and mandible form from the ? pharyngeal arch: ?? that differentiates into bone
1st
Meckel’s cartilage
maxillary process
mandibular arch
pharyngeal arches
frontonasal prominence
stomatodeum
what is the stomatodeum?
developing oral cavity
pharyngeal arches
cardiac swelling
the pharyngeal arches only form what?
the face, nasal cavities, the mouth, the larynx, pharynx and neck
In week ? the ? pharyngeal arch enlarges and overgrows the ? and ? arches forming an ?? called the ??
5
2nd
3rd
4th
ectodermal depression
cervicular sinus
End of week ? the ?, ? and ?pharyngeal grooves and ?? disappear giving a ??
7
2nd
3rd
4th
cervical sinus
smooth contour
remember
Typical pharyngeal arch contains
Ectoderm - outside
Endoderm - inside EXCEPT 1st arch
Aortic arch - artery that arises from the trunk of the primordial heart
Cartilaginous rod - forms the skeleton of the arch
Muscular components - differentiates into the muscles of the head and neck
Nerve - supplies the mucosa and muscles derived from the arch
what determines which type of neural crest cell develop and migrate into the pharyngeal arches?
Different neural crest cells in each pharyngeal arch leading to different developments
homeobox genes
remember
what is the name of the 1st pharyngeal arch?
mandibular arch
what cartilage is in the 1st pharyngeal arch?
meckel’s cartilage
what bones develop from the 1st pharyngeal arch?
incus and malleus
what muscles develop from the 1st pharyngeal arch?
of mastication and anterior belly of digastric
what ligaments develop from the 1st pharyngeal arch?
sphenomandibular and sphenomalleolar
what nerve develops from the 1st pharyngeal arch?
CNV - trigeminal nerve
what artery develops from the 1st pharyngeal arch?
maxillary
what occurs from a 1st pharyngeal arch abnormality?
treacher collins syndrome
what is the 2nd pharyngeal arch called?
hyoid arch
what cartilage develops from the 2nd pharyngeal arch?
Reichert’s cartilage
what bones develop from the 2nd pharyngeal arch?
stapes, lesser horn and body of hyoid, styloid process
what ligaments develop from the 2nd pharyngeal arch?
stylohyoid ligament
what muscles develop from the 2nd pharyngeal arch?
muscles of facial expression and posterior belly of digastric
what arteries develop from the 2nd pharyngeal arch?
hyoid artery and stapedial artery
what nerve develops from the 2nd pharyngeal arch?
CNVII - facial nerve
what bones develop from the 3rd pharyngeal arch?
greater horn of hyoid, body of hyoid
what muscles develop from the 3rd pharyngeal arch?
stylopharyngeus
what nerve develops from the 3rd pharyngeal arch?
CNIX - glossopharyngeal
what artery develops from the 3rd pharyngeal arch?
internal carotid
what arteries develop from the 4th pharyngeal arch?
right subclavian artery and aorta
what nerve develops from the 4th pharyngeal arch?
Vagus nerve
what muscles develop from the 4th pharyngeal arch?
pharyngeal and laryngeal muscles
what bones develop from the 4th pharyngeal arch?
laryngeal cartilages
between the arches there are pouches
what does the 1st pouch form?
middle ear
between the arches there are pouches
what does the second pouch form?
supratonsillar fossa
between the arches there are pouches
what does the third pouch form?
thymus and inferior parathyroid gland
between the arches there are pouches
what does the 4th pouch form?
superior parathyroid gland
and
post-branchial body
a Branchial fistula/cyst on SCM muscle is a result of what?
2nd arch fails to grow
ectopic thymic or parathymic tissue is a result of what?
parathyroid tissue doesn’t migrate, parathyroid gland closer to the mouth
what does the 1st and 2nd pharyngeal groove turn into?
external auditory meatus
what does the 2nd, 3rd, and 4th pharyngeal groove temporarily turn into?
cervical sinus -> temporary
understand this overview
understand this overview
