pharyngeal arches Flashcards
when do the pharyngeal arches form
4th week of development
What are the four parts of the pharyngeal arches ?
arch
pharyngeal pouch
clefts or groves on outside
membrane
A typical pharyngeal arch contains
artery
nerve
cartilage
muscular
What two prominences form the first arch
mandibular and maxillary prominences
what nerve is from the first arch
trigeminal CV nerve
what nerve is from the second arch
facial nerve CVII
third arch forms what nerve
glossopharyngeal nerve
what muscles are derived from the first arch
mylohyoid and anterior belly of the digastric and tensor tympani and tensor veli palatini
what muscles form from the second arch
stepedius and stylohyoid and posterior belly of digastric
what muscles form from the third arch
stylopharyngeus
the fourth and sixth arches give rise to
vagus nerve
what muscles are derived from fourth and six arches
laryngeal, pharyngeal, constrictors, levator veli palatini, skeletal muscle of esophagus
the fourth arch gives rise to what part of laryngeal muscles
cricothyroid (superior laryngeal nerve)
the 6th arch gives rise to
the rest of the laryngeal muscles (recurrent laryngeal nerve)
the malleus and incus are from what arch
first
the stapes, styloid process, lesser horn, superior portion off body of hyoid is from
second arch
greater horn, inferior portion of body of hyoid is from
third
laryngeal cartilage is from
fourth arch and 6th
treacher’s collins syndrome
first arch syndrome
malar/mandibular hypoplasia, down slanting palepebral fissures, malformed external ears
robins sequence
first arch syndrome, micrognathia, cleft palate and glossoptosis
1st pharyngeal pouch gives rise to
tympanic membrane and paryngotympanic tube, ear drum
2nd pharyngeal pouch gives rise to
palatine tonsil and tonsilar fossa
superior 3rd pharyneal pouch gives rise to
inferior parathyroid gland
inferior 3rd pharyngeal pouch gives rise to
thymus gland
superior fourth arch gives rise to
superior thyroid gland
inferior fourth arch gives rise to
ultimobranchial body (calcitonin)
pharyngeal groove 1 gives rise to
tympanic membrane and external auditory canal
pharyngeal groove 2 gives rise to
cervical sinusd
where is the most common location for ectopic thyroid tissue
at base of tonque
pharyngeal arches are lined with
endoderm
pharyngeal grooves are lined with
ectoderm
what produces the opening from the pharynx to the amnionic cavity
oropharyngeal membrane
when do the salivary glands develop
7th week
parenchyma of the salivary glands is from
neural crest cells
what is the muscular component of the pharyngeal arch from ?
somitomeres
middle part of the first arch gives rise to
anterior ligament of malleus and sphenomandibular ligament
what is the first endocrine gland to form
thyroid gland
what is the connection between the tongue and the thyroid?
glossopharyngeal duct
branchial cysts/fistula
results from the persistence of the pharyngeal grooves; branchial fistulas occur when the second arch fails to grow over the third and fourth arches, formation of a lateral cervical cyst; fistulas have an external opening on the lateral aspect of the neck
branchial vestiges
normally pharngeal cartilages disappear; remnants of cartilage or bony elements under the skin anterior to the inferior 1/3 of the sternocleidomastoid persists
ectopic thyroid tissue
remnants of thyroid tissue along course of their migration
thyroglossal cysts and sinues
lie in the mdiline of the neck and re a tubule rementat of the thyroglossal duct
neural crest are involved in what two diseases
treacher collins syndrome and pierre robin sequence
digeorge anomaly
involves abnormalities of the heart, parathyroid gland, face, and thymus gland. affected individuals will have congenital heart disease, ususual facial features, low set ears, small jawbone, wide set eyes and without parathyroid glands
somatic sensation from anterior 2/3 is from
CN V
visceral sensation from anterior 2/3 is from
CN VII
CN IX provides sensory to
posterior 1/3 of tongue
CN X carries
taste from the root of the tonque
