Session 5 Flashcards
What is each arch equal to?
Building blocks of head and neck and how many?
What do they consist of and what supplies them?
1 body segment.
5 Mesenchymal based arches 1-6 with no 5.
Central mesenchyme, then ectoderm(skin/arch) and endoderm(pharyngeal pouches).Each arch has its own nerve/artery/cartilage bar.
What cranial nerves supply the arches in order?
CNV, VII, IX, X, XII
Muscular derivatives of each arch?
1st. Muscles of mastication
2nd. Muscles of facial expression.
3rd. Stylopharangeus.
4th. Levator Palatine, cricothyroid
6th. Intrinsic muscles of larynx
What develops the cartilage bar in the arches?
Name the cartilage bar derivatives
Neural crest cells
1-Meckels(malleus/incus/mandible)
2-Reicherts(Stapes/upper hyoid)
3-hyoid bone
4/6-cartilage of larynx
Aortic sac lies on floor of pharynx so what do the arches become?
1/2- disappear
3-internal carotid
4-arch of aorta (L) and brachiocephallic artery (R)
6- pulmonary trunk
What lines the pockets of the arches in the pharynx?
What does the first pouch become?
What do the other pharyngeal pouches become?
Endoderm.
Tympanic cavity.
The palatine tonsils,parathyroid glands and thymus.
What happens To the pharyngeal clefts?
Remnants of clefts can form?
Where do they form?
The second grows down covering all the others while to 1st develops into the external acoustic meatus.
Branchial cysts.
Anterior-laterally to the SCM
What drives the development of the face?
What surrounds the ventro-lateral surface of the forebrain?
What does the facial primordia consist of?
Cranial neural tube.
Frontonasal prominence.
FNP and the 1st pharyngeal arch.
Describe the components of the face after week 4?
FNP top. A bucopharangeal membrane in the middle called the stomatodeum.
Then the first pharyngeal arch splits into the maxillary prominence and mandibular prominence.
What does the FNP form?
What does the maxillary prominence form?
Mandibular prominence?
Forehead,Nose, philtrum
Cheeks, Lat upper lip, lat upper jaw
Lower lip and jaw
How does the nose form?
How are the nasal prominences fused closer together?
Nasal placodes form on frontal nasal prominence, they sink into nasal pits and the medial and lateral nasal prominences form on either side.
The maxillary prominences grow medically and fuse with the medial nasal prominences and then these medial nasal prominences fuse at the midline creating the intermaxillary segment.
What does the maxillary prominence give rise to?
How does the nasal septum form?
Two palatal shelves which grow vertically down into the oral cavity.
The palatal shelves fuse and the septum grows downwards and fuses with the palatal shelves.
What forms the primary palate?
What forms the secondary palate?
Inter-maxillary segment
Palatal shelves
What forms a lateral cleft lip?
Cleft lip and cleft palate?
Failure of fusion with medial nasal prominence and maxillary prominence.
Failure of palatal shelves to meet at midline.
What does fusion of the intermaxillary prominence and the medial nasal medial prominence form?
Primary palate, philtrum, upper jaw
