Branchial and aortic arch derivatives Flashcards
What embryonic germ layer gives rise to the branchial clefts?
Cleft = eCtoderm
What embryonic germ layer gives rise to the branchial arches?
Arch = Mesoderm (in the middle)
What embryonic germ layer gives rise to the branchial pouches?
Pouch = Endoderm
What does the 1st branchial cleft become?
External auditory meatus
What do branchial clefts 2-4 become?
Form temporary sinuses in the developing fetus which are then obliterated.
If they persist they for branchial cleft cysts located in the lateral neck that don’t move with swallowing
What does the 1st branchial pouch form?
- Middle ear cavity
- Eustachian tube
- Mastoid air cells
What does the 2nd branchial pouch form?
Epithelial lining of the tonsils
What does the 3rd branchial pouch form?
Inferior parathyroid glands and thymus
What does the 4th branchial pouch form?
Superior parathyroid glands
What 3 types of structures develop from each branchial arch?
- Cartilage
- Muscle
- Nerve
What cartilaginous structures develop from the 1st branchial arch?
- Meckles cartilage
- Mandible
- Mandibular ligaments
- Malleus
- Incus
- Vomer
- Palatine
- Zygoma
What muscular structures develop from the 1st branchial arch?
- Muscles of Mastication (Masseter, medial pterygoid, later pterygoid, and temporalis)
- Mylohyoid
- Tensor tympani
- Tensor veli palatini
- Anterior 2/3 of Tongue
What nervous structures develop from the 1st branchial arch?
Mandibular and Maxillary branches of CN V
What cartilaginous structures develop from the 2nd branchial arch?
- Stapes
- Styloid Process
- Stylohyoid ligament
- LeSSer horn of the hyoid
What muscular structures develop from the 2nd branchial arch?
- Muscles of facial expreSSion
- Stapedius
- Stylohyoid