pharyngeal Flashcards
What is the foregut divided into
what organs arise
Cranial part- oral cavity proper
-SM and SL salivary glands
-Pharyngeal apparatus
- respiratory system
Caudal part- oesophagus
- stomach
- duodenum up to opening of CBD
- liver, pancreas, gall bladder
How many pharengyl arches are there
6 but 5th disappaers
by week 4: 6th is rudemntiary so theres 4 arches
What does each pharengyl arch contaim
artery, nerve, cartilage, mesecgymal core, pharengyl cells and arches
Where do the first three arches develop from
neural crest cells.
where do the 4-6th arches develop from
lateral plate mesoderm
What is derived from 1st cartilage
meckels
Incus
malleus
anterior ligament of malleus
Spine of sphenoid
sphenomandibular ligament.
Genial tubercles of mandible
What comes from the 2nd arch cartilage
Stapes
styloid process
stylohyoid ligament,
smaller cornue of hyoid bone
superior half of body of hyoid bone.
What comes from third arch cartilage
Greater cornue and remaining lower part of
body of hyoid bone
What comes from 4th -6th arches
Cartilages of larynx
Nerve supply arch 1
chorda tympani is a pretrematic branch
runs along caudal border
Nerve supply arch 2
facial (CN7)
Nerve supply arch 3
Glossopharengyl (CN9)
Nerve supply arch 4
superior laryngeal
nerve
Nerve supply arch 6
recurrent laryngeal
nerve
Muscles dervied arch 1
eight muscles -> name innervation
muscles of mastication:
Masseter.
Temporalis.
Lateral pterygoid.
Medial pterygoid.
mylohyoid
anterior belly of digastric
tensor palati
tensor tympani
innervated by mandiubular nerve
Muscles derived arch 2
name nerve
Muscles of facial expression
Frontalis
Nasalis
Orbicularis oris
Buccinator
Depressor anguli oris
platysma
stylohyoid
posterior belly of digastric
stapedius.
innervated by facial nerve
named a few facial expression muscles
Muscles dervived arch 3
muscle + innervation
Stylopharyngeus
glossopharyngeal nerve
muscles from arch 4 + 6
Muscles of palate except tensor
palati
Muscles of pharynx except stylopharyngeus
Muscles of larynx
innervated by vagus
what comes from 1st pharengyl cleft
external auditory
meatus and canal, outer
surface of tympanic
membrane
what congential abnromalties can you get with the clefts
Branchial cyst
internal opening of the branchial sinuses arising from incomplete removal in embryogenesis
- Branchial sinus
- Branchial fistula
A complete fistula is a tract that has an internal opening and an external opening
pharengyl pouches derivatives
1-4
pouch 1: auditory tube + middle ear
Pouch 2: palatine tonsils
pouch 3:parathyroid gland inferior + thymus
Pouch 4: parathyroid superior + ultimobrachial body
Develop in a cranio-caudal sequence
5th rudiemntary
How does external ear devlop
idk
First arch syndrome (mandibulofacial dysostosis)
- Due to failure of proper neural crest cells migration.
- Various congenital malformations of eyes, ears, mandible, palate
Di-George syndrome- CATCH 22
-22q11 deletion
-Improper neural crest cells migration into 3rd and 4th arch
-Cardiac defects (aorticopulmonary septation defects)
Facial abnormalities ,
Thymic aplasia/hypoplasia,
Cleft palate
hypocalcemia due to parathyroid aplasia/hypoplasia
