Lecture 9 : Pharyngeal Arches Flashcards
The pharyngeal apparatus is made up of 4 components:
- arches
- grooves/clefts
- membranes
- pouches
Each arch is lined externally by….
ectoderm
Each arch is lined internally by…
endoderm
The first arch forms a … and … process
maxillary and mandibular
The maxillary process from arch 1 forms: (3)
Maxillary bones
Zygomatic bones
Vomer
The mandibular process from arch 1 forms the… and…
mandible and squamous portion of temporal bone
Skeletal elements of arch 1
- anterior ligament of malleus
- malleus and incus
- sphenomandibular ligament
- Meckel cartilage
Skeletal elements of arch 2
- stapes
- styloid process
- stylohyoid ligaments
- lesser cornu of hyoid bone
- Reichert cartilage
Skeletal elements of arch 3
- body of hyoid bone
2. greater cornu (horn) of hyoid bone
Skeletal elements of 4th and 6th arch
- Thyroid cartilage
2. cricoid cartilage
1st arch muscles
- MOM (temporalis, masseter lateral and medial pterygoid)
- Mylohyoid
- anterior belly os digastric
- Tensor tympani and veli palatini
1st arch muscles are all innervated by…
CNV (trigeminal, V2 and V3)
2nd arch muscles
- Facial expression
- Stapedius
- Posterior belly of digastric
- Stylohyoid
2nd arch muscles are all innervated by…
CNVII (facial)
3rd arch muscle
Stylopharyngeus m.
The 3rd arch muscle, stylopharyngeus m. is innervated by
CNIX (glossopharyngeal)
4th arch muscles
- pharyngeal constrictor mm.
- Levator veli palatini m.
- Cricothyroid m.
4th and 6th arch muscles are innervated by
CNX (Vagus)
6th arch muscle
intrinsic mm. of larynx
Anterior 2/3 of tongue (from 1st arch) is innervated by
CNV-trigeminal, V3 sensory
CNVII-facial- taste
Posterior 1/3 (mostly from 3rd arch) is innervated by
CNIX-glossopharyngeal- sensory and taste
The epiglottis is innervated by
CNX-vagus-sensory and taste
Pouch 3 derivatives- dorsal buds become… and ventral buds become…
dorsal buds- inferior parathyroid glands
ventral buds- fuse together at midline forming thymus
Pouch 4 derivatives- dorsal buds become… and ventral buds become…
dorsal buds- superior parathyroid glands
ventral buds- ultimopharyngeal body
