Function of the nose

A healthy nose can fulfill three essential functions. Firstly, it should warm, pre-clean and humidify the inhaled air. In addition, we identify numerous everyday odors with our fine sense of smell.Therefore our nose also fulfills a certain sense of orientation.

Pleasant smells of tasty food even stimulate our appetite and the production of stomach acid. Unpleasant odors warn us, for example, of spoiled food. Anyone who has a bad cold or who holds both nostrils notices how our voice changes and becomes more “nasal”.

This is because the nose, with its large resonance chamber, provides for speech formation. In addition, a cold causes the nasal mucosa to swell and our sense of smell temporarily fails us. Our lungs can actually only tolerate moist, warm and clean air.

That is why there is a wreath of short nasal hairs in each nostril, which are intended to provide a rough pre-cleaning of the air and can retain dust. Smaller hairs, which we could not see with the naked eye (ciliated epithelium) cover the entire mucous membrane of the nose and are also able to carry out pack strokes in the direction of the throat. Anyone who has a cold is certainly familiar with the unpleasant situation of having a mucous throat.

However, the body wants to keep the nose free for breathing and forces the person to either unconsciously swallow the mucus transported into the throat, which is not too bad, or to spit it out. Although the mucus contains dust as well as many viruses and bacteria that keep our colds going, the stomach acid kills almost every pathogen. The mucosa (Regio respiratoria), which is always moist, is located between the ciliated epithelium and moistens the dry inhaled air.

The film of moisture is formed by goblet cells, which under the microscope actually look like a simple light-colored drinking cup. The warming of the inhaled air is caused by a kind of own heating system of the nose. This is formed by a network of very small blood vessels embedded directly in the nasal mucosa.

As with a central heating system, this network of blood vessels is centrally regulated. When the air is cold, the air should be warmed up, the blood supply to the vessels is increased. Warm air leads to the down regulation of the blood circulation.

The olfactory mucosa (Regio olfactoria) has the special purpose of being able to smell. It is located at the upper turbinates, the nasal roof and the upper part of the nasal septum. Olfactory nerves (Nn.

Olfactorii) collect the information of the odour and bring it through a sieve-like structure (Lamina cribrosa) through the ethmoid bone to the brain. If we want to perceive a fine smell and smell a flower, for example, we start to “sniff”. This slow and short drawing in of air brings especially a lot of current into exactly this area where the olfactory cells are located. If we would simply hold our nose to the rose and breathe deeply, we would probably hardly be able to perceive the smell.