Its sensory division has three parts connecting to sensory receptor sites on the face: 1)The ophthalmic part gives sensation to parts of the eyes, including the cornea, mucosa in the nose, and skin on the nose, the eyelid, and the forehead. 2)The maxillary part gives sensation to the middle third of the face, side of the nose, upper teeth, and lower eyelid. 3)The mandibular part gives sensation to the lower third of the face, the tongue, mucosa in the mouth, and lower teeth