Embroyology= The Development Of The Nose And The Face Flashcards
What drives the development of the face?
Expansion of the cranial neural tube
The appearance of a complex tissue system associated with the cranial gut tube and the outflow of the developing heart
Development of the sense organs
What is the neural crest cells?
A specalised population of cells that orignate within the neuroectoderm, migrate and contribute to a variety of CNS structures, and the cells of the lateral border of the neuroectoderm become displaced and enter the mesoderm
From where is the facial skelton dervived?
The neural crest of the 1st pharyngeal arch
From where are the muscles of facial expression dervivied?
Mesoderm of the 2nd pharyngeal arch
From where are the muscles of mastication dervivied?
The mesoderm of the 1st pharyngeal arch
What structures does the frontonasal prominence create?
The forehead, the bridge of the nose, the philtrum, and the nose
What structures does the maxillary prominence create?
The lateral upper jaw, the lateral upper lip, the cheeks
What does the mandibular prominence create?
The lower lip and the jaw
How does the nose develop?
The nasal placodes appear, then sink to become the nasal pits, medial and lateral nasal prominence form, the maxillary prominences then grow medially, and push the nasal prominences closer to the midline, and the maxillary prominences fuse with the medial nasal prominence, and the medial nasal prominences than fuse in the midline
What factors contibrute to the separation of the oral and the nasal cavities?
Maxillary prominences give rise to two palatial shelves, and grow vertically downwards on each side of the developing tongue =, the the mandible grows large enough to allow the tongue to drop, and the palatal shelves then grow towards one another and then fuse in the midline, and the nasal septum develops and then fuses eventually with the palatal shelves
What are the features of the dual origin of the lip and palate?
The inter maxillary segment that arises from the medial nasal prominences, and therefore the the intermaxillary segment forms the primary palate and then the fused palatial shelves from the maxillary part
How would you get a lateral cleft lip?
Failure of fusion of the medial nasal prominence and the maxillary prominence
How would you get the cleft lip and a cleft palate?
Failure of the fusion of the medial nasal promience and the maxillary promience, and combined with the failure of palatial shelves to meet in the midline,
What is the fate of the mandibular promience?
Forms the lower jaw and lip
What is the fate of the lateral nasal promience?
Forms the sides of the nose
