Formation of Palate and Oral Cavity - Weeks 6-8 Flashcards
What are the structures that appear in the stomodeum in the fifth week that enter into formation of the palate?
Primary palate
Nasal septum
Palatine folds or shelves
What arises from the inner surface of the median nasal facial process?
Primary palate
What arises from the primary palate?
Nasal septum
What arise from the inner surface of the maxillary facial processes?
Palatine folds
That palatine folds or shelves have lining epithelium that is connected to an underlying mesenchymal tissue also called what?
ectomesenchyme, it originates in the ectoderm primary germ layer
Palatine folds move from a vertical position to what?
a horizontal position above the tongue
Mesenchyme tissue of the palatine folds and nasal septum flow _____?
towards each other
Epithelial fusion happens in what week?
The 6th
What does epithelial fusion begin with?
Fusion of the primary palate with the palatine folds.
Epithelial fusion progresses in what direction?
Posteriorly
Epithelium of the palatine folds fuse with each and with the epithelium of what?
the nasal septum
Mesenchymal tissue is in the confines of what?
the palatine folds and the nasal septum
The fused epithelium breaks up to allow what?
The union of the mesenchyme of the palatine folds and nasal septum
Once the epithelium is gone, the mesenchyme union is complete and what is formed?
The secondary palate, the oral and nasal cavities are present
Name 3 events that happen in the 4th week.
1- Rupture of buccopharyngeal membrane
2- Appearance of tongue
3- Disappearance of branchial arches
