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The nose prepares every breath for the lungs. Its lining warms and moistens the incoming air, while hairs and sticky mucus catch dust and pollen, so by the time the air reaches the lungs it is close to body temperature and almost fully humidified.

Respiratory science

Health

The story behind the card

Much of this work happens on the nasal conchae, three curled shelves of thin bone on each side of the nose, covered in a lining rich in blood vessels. They split the airflow into narrow channels and give it a large, warm, moist surface to pass over. Tiny hair-like structures called cilia then sweep the trapped dirt, caught in mucus, towards the throat, where it is swallowed. Most people also have a nasal cycle: every few hours one side of the nose swells slightly while the other opens up, so the two sides take turns doing most of the work. Breathing through the mouth skips much of this conditioning, which is one reason it can leave the throat feeling dry.

Türkçe oku
Burun her nefesi akciğerler için hazırlar. Burnun iç yüzeyi içeri çekilen havayı ısıtıp nemlendirir; burun kılları ve yapışkan salgı (mukus) da tozu ve poleni tutar. Böylece hava akciğerlere ulaştığında vücut sıcaklığına yakın ve neredeyse tamamen nemlenmiş olur.

Bu işin büyük bölümü burun konkalarında yapılır. Konkalar, burnun her iki yanında üçer tane bulunan, kıvrık raflara benzeyen ince kemiklerdir ve bol damarlı bir zarla kaplıdır. Havayı dar kanallara bölerek geniş, ılık ve nemli bir yüzeyin üzerinden geçirirler. Mukusa yapışan kiri de titrek tüy denen kıl benzeri minik yapılar boğaza doğru süpürür; kir oradan yutulur. Çoğu insanda bir de “burun döngüsü” vardır: Birkaç saatte bir burnun bir yanı hafifçe şişer, öbür yanı açılır; böylece iki taraf işi sırayla üstlenir. Ağızdan nefes alınca bu hazırlığın büyük kısmı atlanır; ağızdan soluyanların boğazının kurumasının bir nedeni de budur.

Sources and further reading

Background reading: Nasal breathing
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