The Nose
On both sides of the septum are rounded ridges,
called turbinates, outgrowths of soft bone covered with mucous membrane. Air is
warmed and moistened in the turbinates, and the sticky surface of mucous
membrane catches any foreign particles that have gotten by the nostril hairs.
The mucus, which is continuously secreted by the membranes covering the
turbinates, drains into the throat.
In addition to
the mucus, the membrane contains hairlike filaments, called cilia, which wave
back and forth a dozen times a second, helping to clean incoming air and move
foreign particles trapped in the mucus down the back of the throat and into the
stomach where impurities are inactivated by gastric acid.
Extending into the nasal cavity from the base of the
skull are large nerve filaments which are part of the sense organ for smell.
From these filaments, information on odors is relayed to the olfactory nerve
which goes to the brain.
THE SINUSES
The sinuses are
cavities lined with mucous membranes which are continuous with those lining the
nose. There are eight sinuses: the frontal on each side of the forehead; the
maxillary in the cheekbones on each side; the ethmoidal in the walls between
nasal cavity and eye sockets; and the sphenoidal behind the nasal cavity.
Filled with air, the sinuses lighten the head bones.
They help equalize air
pressure in the nasal cavity, aid in warming and moistening air, and serve as
sounding chambers to give resonance to the voice. Many of us undoubtedly would
be happy to do without the sinuses if we could be spared the pain of sinus
infections-for, linked as closely to 208 / Preventive Body Care the nasal
cavity as they are, the sinuses can be affected by infection spread from the
nose. It is worth noting here that excessively hard nose blowing is a factor in
spread of infection to the sinuses.
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