Page 86 - Consciousness in the Cell

CONSCIOUSNESS IN THE CELL

TINY HAIRS OF THE RESPIRATORY SYSTEM

FAULTLESSLY DETERMINE DIRECTION

Along with air, we actually breathe in a lot of dust. But this and
many other substances harmful to the body are held at certain
"security zones" where they are neutralized before they ever get a
chance to reach the lungs.
From the nose to the bronchioles, the entire surface of the res-
piratory pathway is coated with a layer of mucus. This substance,
which also acts as a moisturizer for the respiratory surface, also
traps small breathed-in particles like dust, preventing them from
reaching the lungs. After these foreign particles have been caught
by the mucus, however, they must be ejected out of the body, lest
they build up in the respiratory passages. To effect this, another
security mechanism comes into play.
Lining the respiratory surfaces are sharp-pointed flagella
known as cilia, approximately 200 present on each cell. By whip-
ping back and forth in waves, from ten to twenty times a second,
these cilia facilitate regular movement—always up towards the
pharynx. This way, any mucus that has trapped foreign particles
is directed towards the pharynx at a rate of one centimeter per
minute.
In the nose, however, mucus needs to be directed downwards,
and so the cilia move in the opposite direction. This way, any for-
eign matter in the nasal mucus is also moved towards the phar-
ynx. Later on, any foreign matter is either swallowed along with
the mucus and taken to the digestive system, or expelled from the
body through coughing.
As these examples show, these tiny hairlike structures can
determine the location of the pharynx which is, relatively speak-
ing, quite a distance away, even though they have no eyes to see

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