Sagittal section of nasal region: frontal sinus  |  superior concha of ethmoid bone |  middle choncha of ethmoid bone | inferior concha (a separate bone) |  eustachian (pharyngotympanic or auditory) canal |  pharyngeal tonsil | uvula | palatine bone | hard palate (palatine process) of maxilla | Brain Structures:  corpus callosum | trigeminal nerve | optic chiasma |