GENERAL HISTOLOGY

Detailed explanation-1: -The intraosseous duct transits through the maxillary bone. Its medial border is formed by the ethmoid bone superiorly and the inferior turbinate inferiorly. It is about 12 mm long and 3 to 5 mm wide. It opens into the inferior meatus at the valve of Hasner.

Detailed explanation-2: -Lacrimal fossa (or lacrimal sulcus; fossa for lacrimal sac) – depression along the junction of the lacrimal bone and maxilla bone that holds the lacrimal sac; tears formed by the sac drain through a duct into the nasal cavity.