Nasal Cavity and Air Sinuses Flashcards
The external nose is made primarily of what?
cartilage
What are the different cartilages of the external nose?
two large lateral nasal cartilages and two greater alar wing cartilages
-also a number of smaller cartilages and soft tissue
What is bony portion of the nose referred to as?
the bridge of the nose
What comprises the bony portion of the nose?
two nasal bones on either side of the midline, a portion of frontal bone, and a portion of maxillary bones
What divides the nasal cavity into right and left?
nasal septum
How do the nasal cavities communicate anteriorly?
through the external nares (nostrils)
What marks the opening of the nasal cavity?
the external nares
What guards the opening of the nasal cavity?
coarse hairs in the external nares that keep out debris from the environment
How do the nasal cavities communicate posteriorly?
internal nares or choanae
Where are the internal nares located?
just before the nasopharynx, the portion of the pharynx closest to the nasal cavity
What makes up the medial wall of the nasal cavity (nasal septum)?
- vomer
- perpendicular plate of ethmoid bone
- septal cartilage
What is the roof of the nasal cavities?
- nasal bones
- frontal bone
- ethmoid bone
- sphenoid bone
The rood of the nasal cavities is perforated by what?
cribriform plate of the ethmoid bone through which the olfactory axons called filia olfactoria pass into the olfactory bulb
What lies above the roof of the nasal cavities?
the anterior cranial fossa
What makes up the floor of the nasal cavities?
- palatine process of the maxilla anteriorly
2. horizontal plate of the palatine bone posteriorly
The floor of the nasal cavities separates it from what cavity?
oral cavity
What makes up the lateral wall of the nasal cavities?
- frontal process of the maxilla
- palatine bone
- sphenoid bone
What structures are superimposed (laid over) the lateral wall of the nasal cavities?
lacrimal, ethmoid, and inferior nasal concha
What are nasal concha?
3 sea-shell shaped thin bony ridges that protrude out into the cavity in a gentle curve; superior, middle, inferior conchae
Which two nasal concha are associated with the ethmoid bone and which one is independent?
superior and middle, inferior is independent
What is a nasal meatus?
a space under each nasal concha; superior, inferior, and middle meatuses
What is the purpose of the meatuses?
each meatus is a site of drainage for one or more of the four paired paranasal air sinuses or the nasolacrimal duct
What are the four paired paranasal sinuses?
- frontal
- maxillary
- sphenoidal
- ethmoidal air cells (anterior, middle, and posterior groups)