The Nasal Cavity


External opening: Nostril

Posterior opening: Choanae

Inferior: Hard palate

Superior: Anterior part of cranial base


Subdivisions of each nasal cavity
  • Vestibule : Between the alae and septum. Lined by skin with vibrissae to filter coarse particles.

  • Respiratory portion : Most of the nasal cavity lined by respiratory epithelium

  • Olfactory portion: Area over superior concha and superior part of nasal septum. Lined by olfactory epithelium.

What are the microscopic differences between olfactory adn respiratory epithelium?


Walls of nasal cavity  
  • Floor: The palate
  • Roof: Frontal bone, nasal bone, cribriform plate of ethmoid, body of sphenoid.
  • Medial wall: Nasal septum
  • Lateral Wall:
    • Bones: Nasal, lacrimal, maxilla (alar and lateral cartilages)
    • Conchae: Superior and middle are parts of the ethmoid bone. Inferior is a separate bone.

The Nasal Cavity and Paranasal Sinuses