What is nasal passage?
Nasal Passages- Paired, convoluted passages behind the external nose, leading from nostrils to nasopharynx.
- Divided by the nasal septum into right and left sides.
- Lined by mucous membrane throughout, except in olfactory region.
- Air entering nasal cavity is deflected by turbinates, providing thorough contact w/ mucous membranes.
- Nasal Meatus - The curved space between one nasal concha and the lateral wall of the nasal cavity. There are three meatuses: superior, middle, and inferior.
- Nasal Conchae - Thin projections of bone covered by mucous membranes, which serve to increase the surface area of the nasal cavity and promote turbulence of incoming air for olfactory sampling. There are three conchae: superior, middle, and inferior.
- Nasopalatine nerves and branches of maxillary trigeminal nerve provide sensation to nasal passages.
- Maxillary artery, anterior ethmoidal artery, and sphenopalatine artery provide arterial supply.
- Pterygoid venous plexus, through facial vein, provides venous drainage.
FUNCTIONS OF NASAL PASSAGES:
- Protection: The nasal passages protect the respiratory system by filtering dust, pollen, and other particles from the air.
- Warming and Humidifying Air: The nasal passages help warm cold air and humidify dry air, making it more comfortable for the lungs.
- Olfaction: The nasal passages are responsible for the sense of smell. Odor molecules are detected by receptors in the olfactory epithelium, which is located in the roof of the nasal cavity.
- Resonance: The nasal passages help to produce resonance, which gives the voice its characteristic sound.
- Protection of the brain: Through the cribriform plate, some of the cranial nerves enter the brain.