Lecture 32: Development of Head and Neck I Flashcards
What cells generally gives rise to structures in the craniofacial region?
Neural crest cells
Name the early primordia for the facial region
Frontonasal prominence, ectodermal nasal placodes, maxillary and mandibular processes
What is the pharyngeal arch tissue derived from mesoderm of somitomeres?
Musculature
What is responsible for pharyngeal arch mesenchyme (except for musculature)?
Neural crest
Expression of what group of genes is responsible for segmentation of cranial neural tube?
Hox genes
What signals the prepatterning of cranial ectoderm?
FGF-8
What is responsible for patterning endoderm of the first pharyngeal pouch?
Otx2
What is responsible for patterning the endoderm of pharyngeal pouches 2-4?
Retinoic acid
What group of genes heavily influence dorsoventral patterning of pharyngeal arches?
Dlx genes
The frontonasal ectodermal zone is induced by Shh from which area?
A. Forebrain
B. Midbrain
C. Hindbrain
D. Pharyngeal arches
A. Forebrain
What is the primary function of the FGF-8/Shh gradient in the frontonasal ectodermal zone?
Shaping of the tip of the snout
What are the primordia of the face?
Frontonasal prominence, nasomedial processes, nasolateral processes
What are the primordia for the jaws?
Maxillary processes, Mandibular processes, Meckel’s cartilage
What is responsible for subdivision of the first pharyngeal arch into upper and lower jaw primordia?
Endothelin-1
What are the derivatives of Meckel’s cartilage?
Articular and Quadrate cartilages
What is Meckel’s cartilage derived from?
Neural crest
What does the quadrate bone become in mammals?
Incus
What does the articular bone become in mammals?
Malleus
Expression of what gene is involved in the formation of the temporomandibular joint in mammals?
Barx-1
What are the primordia for the palate?
Unpaired median palatine process (premaxilla), paired lateral palatine processes (secondary plate)
Hypoplasia of the mandible and facial bones is commonly associated with an autosomal dominant condition involving the TCOF1 gene. In this condition, there is a reduced population of neural crest cells in the 1st pharyngeal arch. This condition is associated with which of the following anomalies?
A. Treacher-Collins Syndrome
B. Waardenburg Syndrome
C. Ankyloglossia
D. DiGeorge Syndrome
A. Treacher-Collins Syndrome
Which of the following is derived from Rathke’s pouch?
A. Thyroid
B. Diencephalon
C. Adenohypophysis
D. Olfactory epithelium
C. Adenohypophysis
The auditory tube is a derivative of which pharyngeal pouch?
First pharyngeal pouch
