Pharyngeal Arches Flashcards
What is meckels cartilage also known as?
Cartilage of PA 1
What 3 things does meckels cartilage form?
- ) Malleus & incus
- ) Anterior ligament of malleus
- ) Sphenomandibular ligament
The cartilage of PA 2 is also known as?
Reichert Cartilage
What is formed from Reichert cartilage?
- ) Stapes
- ) Styloid process of the temporal bone
- ) Lesser horn of the hyoid bone
The cartilage of PA 3 forms what?
- ) Body of the hyoid bone
- ) Greater horn of the hyoid bone
- ) Thyroid cartilage
- ) Cricoid cartilage
The body of the hyoid bone is formed from?
The hypo pharyngeal eminence
The 4th and 6th cartilages form what?
The laryngeal cartilage
The first arch forms what muscles? What nerve?
The muscles of mastication. CN V
The second arch forms what muscles? What nerve?
The facial muscles. CN VII
The third arch forms what muscles? What nerve?
Stylopharyngeus m. CN IX
The fourth arch forms what muscles? What nerve?
Cricothyroid, levator veli palatini, and constrictors of the pharynx. CN X
The sixth arch forms what muscles? What nerve?
Intrinsic muscles of the larynx. CN X
Each pharyngeal arch is supplied by what nervous structure?
Its own CN
What are special visceral efferents?
Supply muscles derived from the arches
What are special visceral afferents?
Supply dermis and mucous membranes of the head and neck
The trigeminal nerve supplies which arch?
The first arch
The facial nerve supplies which arch?
The second arch
The glossopharyngeal nerve supplies which arch?
The third arch. Stylopharyngeus m.
The vagus nerve supplies which arches?
Arches 4-6.
Aortic arch system initially consists of?
5 pairs of arteries that arise from the aortic sac
The primordial pharynx is derived from what?
Foregut
What are the pharyngeal pouches?
5 pairs of pouches
What do pharyngeal membranes do?
Separate pharyngeal pouches from pharyngeal grooves
What does the first pharyngeal membrane become?
The tympanic membrane
In general, what does the first pharyngeal pouch become?
Auditory structures
Specifically, what does the first pharyngeal pouch become?
- ) Part of the TM
- ) The pharyngotympanic tube
- ) Tubotympanic recess -> tympanic cavity and mastoid antrum
In general, what does pharyngeal pouch 2 form?
Tonsils, tonsil crypts, lymphatic tissue
What does the 3rd pharyngeal pouch form?
The inferior parathyroid gland and thymus
What does the 4th pharyngeal pouch form?
The superior parathyroid gland
The first pair of pharyngeal grooves becomes what?
The external auditory meatus
What do pharyngeal grooves 2-4 lie in?
The cervical sinus
What are cervical (branchial) cysts?
Remnants of the cervical sinus
The thyroid gland forms from what?
The thyroid primordium
The thyroid gland is connected to the tongue via what structure?
The thyroglossal duct
The ultimo pharyngeal body forms what?
Parafollicular cells
First arch syndrome is characterized by what phenotypically?
Malformation of eyes, ears, mandible, and palate
Treacher-Collins syndrome is characterized as what?
deformed external ears, lower eyelids, and sometimes inner ears
Pierre robin sequence is associated with what?
hypoplasia of the mandible, cleft palate, and eyes/ears
What is thyroid hemiagenesis?
unilateral failure of thyroid formation
What is DiGeorge syndrome?
Agenesis of thymus and parathyroid glands
