lect 12- pharyngeal apparatus: arches, clefts and pouches Flashcards
are pharyngeal clefts/grooves external or internal
external
are pharyngeal pouches internal or external
internal
what pharyngeal pouch does the palatine tonsil come from
2nd
what pharyngeal pouch does the parathyroid gland (inferior) come from
3rd
what pharyngeal pouch does the parathyroid gland (superior) come from
4th
what pharyngeal pouch does the ultimobranchial body come from
4th
when does pharyngeal cysts form
when the second arch fails to grow over the 3rd and 4th arches, leaving remnants of the cervical sinus
what nerve innervates the derivatives of the 1st pharyngeal arch
trigeminal (5)
what nerve innervates the derivatives of the 2nd pharyngeal arch
facial (7)
what nerve innervates the derivatives of the 3rd pharyngeal arch
glossopharyngeal (9)
what nerve innervates the derivatives of the 4th and 6th arch
vagus
what skeletal structures arise from the 1st pharyngeal arch
maxilla, temporal, zygomatic, mandible, malleus, incus
what skeletal structures arise from the 2nd pharyngeal arch
stapes, styloid process, part of hyoid
what skeletal structures arise from the 3rd pharyngeal arch
part of hyoid
what skeletal structures arise from the 4th pharyngeal arch
part of thyroid cartilage; laryngeal cartilages
what skeletal structures arise from the 6th pharyngeal arch
part of thyroid cartilage
what muscles arise from the 4th pharyngeal arch
cricothyroid, levator veli palatini, pharyngeal constrictors
what muscles arise from the 6th pharyngeal arch
intrinsic muscles of larynx
what chromosome is the mutation responsible for trencher-collins on?
chromosome 5
what are the characteristics of trencher-collins syndrome
downward slanting eyes, small lower jaw, and malformed or missing ears. these anomalies cause hearing, breathing and eating problems
what neural crest cells does diverge syndrome affect
those in arches/pouches 3 and 4
describe the catch 22
cardiac abnormalities, abnormal facies, thymic aplasia, cleft palate, hypoparathyroidism/hypocalcemia
what arch/es are defective with goldenhar (oculo-auriculo-vertebral) syndrome
1st and 2nd
what does the thymus arise from
3rd pouch to anterior mediastinum
what does the ultimobranchial body arise from
4th pouch into thyroid gland
what does the ultimobranchial body form
parafollicular (C) cells
what does the pharyngeal pouch 1 give rise to
tympanic cavity (middle ear) and auditory tube
what does pharyngeal cleft 1 give rise to
external auditory meatus
what do remnants of the thyroglossal duct include
the foramen cecum and occasionally thyroglossal cysts
what forms epiglottic swellings
3rd and 4th arches
what forms the copula
2nd-4th arches
what does the 1st arch form
2 lateral and 1 medial swelling (tuberculum impar)
what is the sensory to the posterior 1/3 of the tongue
CN IX
what provides GVA to the anterior 2/3 of the tongue
CN V
what provides SVA (taste) to the anterior 2/3 of the tongue
CN VII
what is the motor innervation to the tongue
hypoglossal (XII)
what is abnormally short frenulum of the tongue resulting in problems with feeding, maintaining oral hygiene, and enunciation
ankyloglossia
what is the issue with a bifid tongue
lateral lingual swellings fail to fuse
what is the issue with macroglossia
hypertrophy of the tongue
what forms the tubotympanic recess
first pharyngeal pouch
where do axons from trigeminal ganglion enter the hindbrain
R2 rhombomere
where does R4 migrate
second arch
where do axons from the geniculate and vestibuloacoustic ganglion migrate
R4
where do R6 and R7 migrate
arches 4 and 6
what axons are at R6 and R7
axons from petrosal and nodose
where is BMP7 expressed
posterior endoderm of each pouch
where is PAX1 restricted to
dorsal-most endoderm of each pouch
where is SHH expressed in reference to the pouches
posterior endoderm of the second and third pouches
what forms the anterior 2/3 of the tongue
lateral swelling outgrowths
how is the anterior 2/3 of tongue separated from the posterior 1/3
terminal sulcus
what provides sensory to posterior 1/3 of the tongue
glossopharyngeal nerve
what are the epiglottis and extreme posterior part of the tongue innervated by
superior laryngeal nerve
what provides special sensory to the anterior 2/3 of the tongue
chords tympani (branch of facial)
what provides special sensory to the posterior 2/3 of the tongue
glossopharyngeal nerve
what is the thyroid gland indicated by
foramen cecum
describe the position of the maxillary and mandibular prominences in reference to the stomodeum
maxillary is lateral; mandibular is caudal
what does the maxillary prominence enlarge to become
to form the cheeks and the maxilla
what is the secondary palate formed by
palatine shelves
what does the mesenchyme of tooth originate from
neural crest
what is the most important molecular factor for tooth patterning
HOX genes
what is most severely altered with robin sequence
mandible
what is the most common deletion sequence in humans
22q11.2 deletion syndrome
what is the mutation with van der wounds syndrome
IRF6