Answer: perpendicular plate
Step-by-step explanation:
The upper portions of the nasal septum is actually formed by the perpendicular plate of the ethmoid bone whereas the lower part is the vomer bone. The ethmoid bone forms the single midline bone that actually forms the lateral wall and roof of the upper nasal cavity. It forms the upper part of the nasal septum and also contributes to the medial walls of the eye orbit. Each side of the nasal cavity looks triangular in shape. It exhibit a broad inferior space that remains narrow superiorly.