The bones maxilla, zygomatic bone, and part of temporal bone originate from which prominence of the first arch?

• A. Maxillary prominence
• B. Mandibular prominence
• C. Frontonasal prominence
• D. Temporal prominence

Answer: (A)

In early development, the face forms from the pharyngeal (branchial) arches, and each arch has a prominence that makes specific facial bones. The first arch splits into two prominences: the maxillary prominence and the mandibular prominence. The maxillary prominence drives the formation of much of the midface and upper jaw, giving rise to the maxilla and the zygomatic bone, and it even contributes to part of the temporal region. The bones listed—maxilla, zygomatic bone, and part of the temporal bone—originate from this maxillary prominence of the first arch. The mandibular prominence forms the lower jaw, while the frontonasal prominence forms the forehead and bridge of the nose.