Embryology Flashcards
What does the first pharyngeal arch become?
External ear
What is a pharyngeal pouch and arch?
Pouch is in the inside, while arch is on the outside
What does the first pharyngeal pouch become?
Internal ear
What do archs 2, 3, 4 become?
Degenerate, or become a cystic remnant
What happens to pharyngeal arch 5?
Never develops in humans
What happens to pharyngeal pouch 2?
Becomes the pouch for the tonsils
What happens to pharyngeal pouch 3? (2 parts)
- Develops into the inferior parathyroid gland
- Thymus
What happens to pharyngeal pouch 4?
Develops into the superior parathyroid gland
What are the pharyngeal membranes?
Thin membrane between each arch
What does the first pharyngeal membrane form?
TM
What do pharyngeal membranes 2, 3, and 4 form?
Degenerate
What structures are formed from the neural crest cells of pharyngeal arch 6?
laryngeal cartilage
What is the role of the Sonic hedgehog gene in development?
Patterning along anterior posterior axis
What is the role of the Wnt-7 gene in development?
Organization along dorsal-ventral axis
What is the role of the FGF gene in development?
Stimulates mitosis of underlying mesoderm to lengthen limbs