THE FUNCTION OF OUR NOSE
FOR SOME REASON PEOPLE DON'T PAY MUCH ATTENTION TO THE NOSE. EXCEPT FOR THE COSMETIC EFFECTS OF ITS SHAPE, IT IS USUALLY REGARDEDAS LITTLE MORE THAN AN OPENING THROUGH WHICH AIR ENTERS. IF THAT WERE ITS SOLE PURPOSE, HOWEVER, PEOPLE MIGHT SUPPOSE THAT IT WOULD BE CONSTRUCTED DIFFERENTLY, IT SHOULD BE WIDE AND OPEN. BUT THE NOSE IS ACTUALLY THE NARROWEST PLACE IN THE RESPIRATORY TRACT. IT IS LIKE A BOTTLENECK, IT IS THE ONE PLACE WHERE THE AIRFLOW IS MOST CONSTRICTED AS THE AIR GOES INTO THE LUNGS. IF YOU COMPARE THE WORK REQUIRED TO PULL THE AIR IN AND OUT OF THE NOSE, IT IS 150 PERCENT OF WHAT IT WOULD BE TO MOVE THE AIR THROUGH THE MOUTH. THIS IS QUITE A DIFFERENCE, AND IT EXISTS EVEN WHEN YOUR NOSE IS NOT STUFFED UP. WHEN WE STOP TO CONSIDER THAT WE BREATHE EIGHTEEN TO TWENTY THOUSAND TIMES A DAY, WE CAN BEGIN TO APPRECIATE THE AMOUNT OF EXTRA WORK DONE IN TWENTY-FOUR HOURS SIMPLY TO GET THE AIR IN AND OUT OF THE NOSE INSTEAD OF THE MOUTH. THIS PROCESS USES A GREAT DEAL OF ENERGY, SO THERE MUST BE A GOOD REASON FOR IT
THERE ARE SEVERAL GOOD REASONS. THE NOSE DOES MUCH MORE THAN SIMPLY LET THE AIR IN. MEDICAL SPECIALISTS WHO HAVE STUDIED DISEASE OF THE NOSE (RHINOLOGISTS) CAN LIST NEARLY THIRTY DISCTINCT FUNCTIONS THAT IT FILTERS, MOISTURIZES, DIRECTS IN OXYGEN, CREATES MUCUS, PROVIDES A ROUTE OF DRAINAGE FOR THE SINUSES, AND AFFECT THE NERVOUS SYSTEM. IT HAS A NUMBER OF OTHER FUNCTIONS, TOO, BUT THERE ARE THE BEST UNDERSTOOD.
ANATOMY AND PHYSIOLOGY
OF THE NOSE
THE WORD NOSE IS ACTUALLY A SOMEWHAT AMBIGOUS TERM. TO THE AVERAGE PERSON IT MEANS THE PROTRUSION VISIBLE ON THE MIDDLE OF THE FACE. BUT TO PHYSICIANS AND PHYSIOLOGISTS IT ALSO MEANS A MYSTERIOUS AND COMPLEX INTERNAL PASSAGEWAY THAT SOMEHOW INVOLVES THE SINUSES AND THE SENSE OF SMELL. FOR THIS REASON IT IS PERHAPS MORE ACCURATE TO THINK OF THERE BEING TWO DISTINCT DIVISIONS OF THE NOSE, THE EXTERNAL AND THE INTERNAL PASSAGEWAYS, WHICH ARE OFTEN INTRICATE AND SERVE A VARIETY OF IMPORTANT PURPOSES, ONLY HUMANS HAVE THIS PECULIAR FACIAL PROTUBERANCE. OTHER ANIMALS HAVE ONLY SIMPLE OPENINGS, OR HOLES, THROUGH WHICH THE AIR ENTERS THE INTERNAL NASAL CAVITY. EVEN OUR CLOSEST RELATIVE, THE APE, DOESN'T REALLY HAVVE A NOSE. WHILE THERE ARE TWO NOSTRILS, THE PROFILE OF A APE SHOWS NOTHING SO PROMINENT AS THE STRUCTURE WE SPORT.
THE SHAPE OF THE EXTERNAL NOSE, HOWEVER, PLAYS AN IMPORTANT ROLE IN PREPARING AIR FOR INHALATION. THIS IS WHY PEOPLE WHO ORIGINATED IN DIFFERENT CLIMATES HAVE DIFFERENTLY SHAPED NOSES. A LONG, BIG NOSE THAT HEATS THE AIR BEFORE IT GETS INSIDE IS CHARATERISTIC OF THOSE WHO LIVE IN COOLER CLIMATES AND ALSO OF THOSE WHO LIVE IN CLIMATES, SUCH AS THE MIDDLE EAST, WHERE THE AIR IS VERY DRY. A WARM, MOIST CLIMATE, ON THE OTHER HAND, REQUIRES MUCH LESS PROCESSING OF THE AIR, MAKING THE WIDE, OPEN NOSTRILS OF THE INHABITANTS OF TROPICAL JUNGLES A RECOGNIZABLE TRAIT.
THE EXTERNAL NOSE ALSO TO GATHER AIR AND ACCURATE ITS FLOW, FORMING A RAPID JET THAT ENTERS THE CAVITY WITHIN THE FACE, THE INTERNAL NOSE. AS WE SHALL SEE LATER, THE WAY THAT THE STREAM OF AIR IS AIMED INSIDE THE HEAD CAN BE OF EXTEME IMPORTANCE. THERE ARE TWO PARTS TO THE EXTERNAL NOSE. ONE PART IS BONE. IF WE FEEL THE BASE OF THE NOSE WE FIND IT TO BE QUITE HAND AND RIGID. MOVING OUTWARD, WE ENCOUNTER A SOFTER AREA. THIS IS MADE OF CARTILAGE. THE FIRST LITTLE COMPARTMENT IN THE EXTERNAL NOSE IS CALLED THE VESTIBULE, AND IT IS FORMED PRIMILARILY BY THE TWO WINGS, OR ALAE, OF THE NOSE WHICH FLARE OUT ON EACH SIDE OF IT. BECAUSE THEY ARE CARTILAGE, AND RELATIVELY FLEXIBLE, THEY TEND TO BE INFLUENCED BY GRAVITY, SO IF WE LIE ON OUR SIDE THE UPPERMOST NOSTRIL WILL TEND TO BE PULLED DOWNWARD AND PARTIALLY CLOSE IN A VALVE-LIKE WAY.
MOVING FURTHER UP THE NOSE, THERE ARE A NUMBER OF SMALL BONES AND CARTILAGES PUT TOGETHER IN AN INTRICATE WAY AND ATTACHED AND CARTILAGES PUT TOGETHER IN AN INTRICATE WAY AND ATTACHED TO A SERIES OF BONES, WHEN THE NOSE IS BROKEN, IT IS ESSENTIALLY THE BONY PARTS AT THE ROOT OF THE NOSE THAT ARE FRACTURED. THE FLEXIBLE PART, HOWEVER, CAN ALSO BE INJURED, PARTICULARLY INTERNALLY. INSIDE AND TOWARD THE TIP OF THE NOSE, THE SETUM, WHICH DIVIDES THE EXTERNAL NOSE INTO TWO PASSEGEWAYS, IS ALSO MADE OF CARTILAGE. FURTHER BACK IT IS BONY. EITHER PART OF IT CAN BE DAMAGED, AND THIS IS MAY RESULT IN THE FAMILIAR "DEVIATED SEPTUM", WHICH TENDS TO CLOSE OFF ONE NOSTRIL AND FAVOR THE OTHER.
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