Week 3 - Embryology of the Head and Neck Flashcards
Carnegie stage 4 Embryo visualised
Carnegie stage 23 Embryo visualised
What does lateral folding do?
Helps bring the gut tube back inside the body
What do Foregut derivatives extend from?
Head to Abdomen
Derivatives of the Foregut
What structures are related to connecting the outside to the inside? i didnt know how to word it properly innit
- Ectoderm and Endoderm only (seen in Oral and Rectal areas)
- Oropharyngeal membrane & cloacal membrane
- These are points of transition
What part of this becomes the head and neck?
The lumps and bumps
What is a Pharyngeal arch?
= Bump with extoderm, mesoderm, endoderm
What is a Pharyngeal crest/fold?
= invaginations of the ectoderm
On diagram -> blue corners into the structure
What are Pharyngeal pouches?
= evaginations of endoderm
On diagram -> yellow corners into structure from inside
What are Pharyngeal Arch Arteries?
= Aortic Arch arteries arising in the region of the pharyngeal apparatus
What do Neural Crest cells give rise to?
Skeletal components
What does Mesoderm give rise to?
Muscular components
What do Aortic Arch Arteries give rise to?
Vascular supply to each of the arches
What does Endodermal layer give rise to?
Pharyngeal pouch components
Do Pharyngeal Arch Cranial Nerves & Arteries elongate and grow into or out of the Pharyngeal apparatus?
Grow INTO the area
What Cranial nerves does the Brainstem give rise to related to the Pharyngeal arch?
Cranial Nerves 5, 7, 9 & 10 -> these are the only ones related to the Pharyngeal Arch -> They grow into a bump of the pharyngeal apparatus
What nerves grow into each bump of the Pharyngeal Arch
Arch 1 -> Trigeminal nerve
Arch 2 -> Facial nerve
Arch 3 -> Glossopharyngeal nerve
Arch 4 -> Superior Laryngeal nerve
Arch 6 -> Recurrent Laryngeal nerve
Is there any crossing of the Cranial Nerves?
Yes -> they are in close proximity to each other during development and may cross