Development of the Face Flashcards
<p>When does face development first begin?</p>
<p>early 4th week</p>
<p>what happens in the early 4th week?</p>
<p>the face is derived from 5 facial prominences surrounding the stomodeum.</p>
<p>what is the stomodeum?</p>
<p>the primitive mouth</p>
<p>what are the facial prominences made up of?</p>
<p>neural crest cells</p>
<p>what are the 5 facial prominences?</p>
<p>1 frontonasal prominence
2 maxillary prominences
2 mandibular prominences</p>
<p>where is the frontonasal prominence?</p>
<p>cranial to stomodeum</p>
<p>where are the maxillary prominences?</p>
<p>lateral to the stomodeum</p>
<p>where are the mandibular prominences?</p>
<p>caudal to stomodeum</p>
<p>what do nasal placeodes develop from and when does this happen?</p>
<p>the ectodermal thickenings on the ventrolateral parts of the frontonasal prominence
occurs in late 4th week</p>
<p>what merges across the midline in the late 4th week?</p>
<p>mandibular prominences</p>
<p>why do the nasal placodes become depressed and when does this happen?</p>
<p>become depressed as mesenchyme surrounding nasal placodes proliferates to form horseshoe shaped elevations
occurs in the 5th week</p>
<p>what do the horseshoe shaped elevations of mesenchyme surrounding the nasal placodes consist of?</p>
<p>2 medial nasal prominences
| 2 lateral nasal prominences</p>
<p>when do the primitive nostrils and nasal cavities develop?</p>
<p>5th week</p>
<p>what are the primitive nostrils and nasal cavities?</p>
<p>in the 5th week nasal placodes invaginate becoming paired nasal pits following the development of the of medial and later nasal prominences</p>
<p>When the maxillary prominences grow medially what does it cause and when does this occur?</p>
<p>it presses the medial nasal prominences to move toward the midline
occurs in 7-10 weeks</p>
<p>the fusion of the medial nasal prominences forms what and when does this occur?</p>
<p>intermaxillary segment
| occurs in 7-10 weeks</p>
<p>what does the intermaxillary segment become and when does this occur?</p>
<p>philtrum
primary palate
medial maxilla
occurs in 7-10 weeks</p>
<p>what forms the secondary palate and when does this occur?</p>
<p>merging of the maxillary prominences
| occurs in 7-10 weeks</p>
<p>what allows for the formation of the upper lip?</p>
<p>fusion between medial nasal prominences and the maxillary prominences</p>
<p>what causes cleft lip and/or palate?</p>
<p>failure of the prominences to fuse</p>
<p>what do the lateral nasal prominences merge and fuse with?</p>
<p>the maxillary prominences</p>
<p>when do the structures of the face develop their characteristic form?</p>
<p>early fetal development</p>
<p>what causes the eyes to shift medially, resulting in their forward-looking orientation</p>
<p>enlargement of the brain</p>
<p>elongation of the mandible causes what?</p>
<p>the ear to appear to rise</p>
<p>what migrate to develop the mm. of facial expression?</p>
<p>myoblasts from the second pharyngeal arch</p>
<p>when is the face fully developed?</p>
<p>the 14th week</p>
<p>facial defects of fetal alcohol syndrome will only occur if the mom drinks when?</p>
<p>during the 1st trimester</p>
<p>levator</p>
<p>elevate</p>
<p>depressor</p>
<p>move it down</p>
<p>labii</p>
<p>associated with lip</p>
<p>anguli</p>
<p>angle of mouth (smile, frown)</p>
<p>superioris</p>
<p>upper lip</p>
<p>inferioris</p>
<p>lower lip</p>
<p>obicularis</p>
<p>sphincter mm. (close eyes, close mouth)</p>
<p>oculi</p>
<p>eyes</p>
<p>oris</p>
<p>upper/lower lip</p>
<p>what are the mm. of the eye?</p>
<p>frontalis, orbicularis oculi, corrugator supercilii mm.</p>
<p>what does frontalis m. do?</p>
<p>raise eyebrow, wrinkle forehead</p>