THE RESPIRATORY SYSTEM EXPALINED.

1. Cribriform plate of the ethmoid bone
2. Pituitary fossa
3. Sphenoidal sinus
4. Vomer
5. Palatine bone
6. Maxilla
7. Septal cartilage
8. Nasal bone
9. Frontal sinus
10. Perpendicular plate of ethmoid bon

Comments
Anatomical: The nasal septum consists, posteriorly, of the perpendicular plate of
the ethmoid bone and of the vomer, anteriorly, of the septal cartilage, superiorly,
of the cribriform plate of the ethmoid bone and of the sphenoid, frontal and nasal
bones and inferiorly, of the maxillary and palatine bones.
Physiological: The septum separates the two nasal cavities.
Clinical: A nosebleed (epistaxis) is due to the expulsion of blood from the nasal
fossae via the choanae (posterior nasal apertures). The common cold or coryza is
due to a highly contagious rhinovirus and is associated with a runny nose
(rhinorrhoea), sneezing, pharyngitis and a low-grade fever.