Neural Tube Closure and Neural Crest Cells

The first branchial groove develops into the external auditory meatus.

Second arch cartilage has an important role in the development of the mandible.

5th arch cartilage gives laryngeal cartilage.

All branchial grooves contribute to the formation of the external auditory meatus.

Vascular components of the fourth branchial arche is aortic arch.

The two lateral nasal processes form the medial sides of the nose.

The nasal septum is formed by the fusion of the two medial nasal processes.

Muscles of mastication are derived from 2nd arch , Muscles of facial expression from 1st arch.

Both maxillary and mandibular processes are derived from the second branchial arch.

At the margins of the nasal placodes, mesenchymal proliferation occurs producing the medial and lateral nasal processes, which form a horse-shoe shape that transform nasal placodes into nasal pits (nostrils) at the 5th wiul.