NEET PG DENTAL EXAM

Detailed explanation-1: -The first pharyngeal pouch develops into the middle ear cavity and the eustachian tube, which joins the tympanic cavity to the nasopharynx. The inner surface of the eustachian tube is covered by a mucosal layer of ciliated cells, supporting cells, secretory cells, and connective tissue.

Detailed explanation-2: -The pinna originates as a fusion of six hillocks. The first three hillocks are derived from the lower part of the first pharyngeal arch and form the tragus, crus of the helix, and helix, respectively.

Detailed explanation-3: -The anatomic space formed by the first pharyngeal cleft between the first and second branchial arches gives rise to the adult external auditory meatus. The space created by the second, third, and fourth pharyngeal clefts gives rise to the adult cervical sinus.