Question
The nerves of the branchial (pharyngeal) arches are derived from:
| A. |
Mesoderm |
| B. |
Endoderm |
| C. |
Neural crest |
| D. |
Neuroectoderm |
|
Correct Answer � C Explanation |
 |
– Neural crest cells originate from the borders of the neural tube & migrate extensively.
– They contribute to various structures, including sensory & autonomic ganglia, Schwann cells, craniofacial bones, cartilage, & cranial nerves of the branchial arches.
– Branchial (pharyngeal) arch nerves arise from neural crest-derived neuroblasts.
Associated Cranial Nerves by Arch:
– First → Trigeminal nerve (CN V3)
– Second → Facial nerve (CN VII)
– Third → Glossopharyngeal nerve (CN IX)
– Fourth & Sixth → Vagus nerve (CN X)
Incorrect Options:
– A. Mesoderm: Forms muscles & connective tissue, not nerves.
– B. Endoderm: Produces epithelial linings, not nerves.
– D. Neuroectoderm: Develops central nervous system structures, not peripheral cranial nerves.