5-Development of Head and Neck
Terms
undefined, object
copy deck
- Motor innervation of muscles derviced from the branchial arches, related to origin from the nucleus ambigous in the CNS are ___.
- SVE or Branchial Visceral Efferent
- Motor innervation of muscles derived from somites are ___.
- GSE
- Fibers which carry taste info from the anterior 2/3 and posterior 1/3 of tongue are ___.
- SVA
- Fibers which carry general sensory info ie from the surface of the head are ___.
- GSA
- What is the extreme cranial end of the foregut known as?
- pharangeal gut or pharynx
- In early development what is the pharynx in direct contact with?
- the ectoderm at the floor of the stomodeum
- What does the contact of the ectoderm with the endoderm of the foregut form?
- oro/buccopharyngeal membrane
- When does the buccopharyngeal membrane break down? What does this allow to connect?
-
4th week of development
primitive oral cavity w/ foregut - What are pharyngeal pouches? When do they form?
-
outpocketings from the endoderm of the pharynx
4th or 5th week - What forms simultaneously with the pouches?
- pharyngeal grooves (clefts)
- What are pharyngeal puches derived from? grooves?
-
pounches-endoderm
grooves-ectoderm - Do the clefts and puches communicate in humans?
- no, they approach each other, but they do not communicate as they do in fish where gills are formed
- What separates the cleft from the pouch in human embryos?
- pharyngeal membrane
- The formation of clefts and grooves divides what?
- the mesenchyme on each side of embryo into six vertical bars called pharyngeal arches
- In humans, which arch degenerates?
- 5
- What does each arch contain?
-
artery
cartilaginous bar
muscle
cranial nerve - Blood vessels of the head and neck are derived primarily from which aortic arch?
- 3, but also 4 and 6
- Mesenchyme of each arch is derived from what?
- neural crest and lateral plate and paraxial mesoderm
- The neural crest derived mesencyme forms the cartilage of each arch and will be responsible for what else?
- formation of the skeletal structures of the head and neck
- Mesenchyme derived from the lateral plate and paraxial mesoderm is responsible for formation of what?
- musculature of the face and neck as well as the dermis of the skin
- The musculature of the arches arises from ____.
- somitomeres
- Which nerve supplies the first arch?
- mandibular division of the fifth CN, some additional supply through the chorda tympani (a branch of VII)
- Which neve supplies the second arch?
- CN VII
- Which nerve supplies the muscles of the third arch?
- CN IX
- Which CN supply arches 4-6?
- CN X and XI
- The fourth arch is innervated by what?
- superior laryngeal branch of the vagus
- The 6th arch is innervated by what?
- recurrent laryngeal nerve
- The nerves which innervate the branchial arch musculature carry SVE fibers to the ____.
- nucleus ambiguos
- What two processes are formed from the mesenchyme in the first pharyngeal arch?
- a short maxillary process and a long mandibular process
- The maxillary process expands _____ into the region below the eye.
- forward (anteriorly and medially)
- The cartilage of the maxillary process retrogresses with the maxilla, zygoma, palatine, and squamous portion of the temporal bone forming _____.
- intramembranously
- The mandibular process of the 1st pharyngeal arch is transformed into ____.
- Meckel's Cartilage
- All put two fragments of the mandibular process retrogress except which two fragments?
- malleus and incus
- The perichondrium of the Meckel's cartilage condenses to form what?
- anteior ligament of the malleus and sphenomandibular ligament
- The mandible forms ____.
- intramembranously
- What does the musculature of the 1st arch consist of?
- muscles of mastication, anterior belly of the digastric, mylohyoid, tensor tympani
- What nerve innervates the first arch?
- mandibular branch of V
- In the second pharyngeal arch, the cartilaginous bar formed is known as what?
- Reichert's Cartilage
- What does the dorsal part of the 2nd pharyngeal arch form?
- stapes, styloid process of the temporal bone
- What does the intermediate portion of cartilage of the 2nd pharyngeal arch form?
- stylohyoid ligament and ventral part of the lesser cornu and the superior part of the body of the hyoid bone
- Name the muscles of the second arch.
- stapedius, stylohyoid, posterior belly of the digastric, muscles of facial expression (including buccinator), the auricular muscles, the occipitofrontalis, and the platysma