T16- Development of the face, PA, and BR Flashcards
What does the pharyngeal apparatus consist of
Pharyngeal arches, pouches, grooves, and membranes
When are the four pairs of pharyngeal arches visible externally
By the end of the fourth week (day 28)
What are the germ cell layers of the PA
Paraxial and lateral plate mesoderm: mesenchymal core
Ectoderm: covers the PA externally
Endoderm: covers the PA internally
What are the muscles of mastication
Temporalis and Masseter
What are the muscles of mastication innervated by
Trigeminal nerve V (V3, the mandibular division)
What are the muscles of facial expression
Buccinator, orbicularis oris, and the obicularis oculi
What are the muscles of facial expression innervated by
The facial nerve (CN VII)
What nerve is responsible for general sensory information from the skin of the external acoustic meatus
The facial nerve (CN VII)
Nerve that innervates stylopharyngeus for swallowing
Glossopharyngeal nerve
Nerve that innervates muscles in throat
vagus nerve
Musles of the first PA
- muscles of mastication
- mylohyoid and anterior belly of digastric
- tenor tympani
- tensor veli palatini
Nerves of the first PA
Maxilary (V2) and mandibular(V3) divison of the trigeminal nerve
Where does the first PA nerve (Trigeminal) recive sensory information from
superficial sensory information from the face and deep sensory information from the nasal cavity
Aortic arch artery of first PA
largely disappears and remnants form part of the Maxillary artery
What does the dorsal part of the cartilaginous rod form in the first PA
malleus and incus
What does the middle part of the cartilaginous rod form in the first PA
Anterior ligament of the malleus and the sphenomandibular ligament
What does the ventral part of the cartilaginous rod form in the first PA
primordium of the mandble
Muscles of second PA
- muscles of facial expression
- stapedius
- stylohyoid
- posterior belly of digastric
Nerves of the second PA
Facial nerve (CN VII)
Aortic arch arteries of the second PA
largely disappear but dorsal parts form the stems of the small stapedial arteries
What does the dorsal part of the cartilagenous rod in the second PA form
stapes and styloid process
Second PA
What does the middle part of the cartilagenous rod form
The middle part of the cartilagenous rod regresses but the perichondrium forms as the stylohyoid ligament
Second PA
What does the ventral part of the cartilagenous rod form
The lesser cornu (horn) of the hyoid bone
Muscle of the third PA
stylopharyngeus
Nerve of the third PA
glossopharyngeal (CN IX)
What does the glossopharyngeal nerve recive sensory information from?
The larynx and esophagus
What does the proximal part of the aortic arch artery in the third PA bcome
the common carotid artery
What does the distal part of the aortic arch artery in the third PA become
The internal carotid artery
What does the cartilagenous rod of the third PA become
The greater cornu (horn) of the hyoid bone
Where does the body of the hyoid bone come from
The hypopharyngeal eminence
What do the muscles of the 4th and 6th PA form
Muscles of larynx, pharynx and esophagus
What innervates the 4th PA
superior laryngeal branch of the vagus nerve (CN X)