> Introduction to Nose

Long or short, sharp or flat, noses are designed to moisten, warm, and filter air before it is drawn into the delicate recesses of the lungs. With every breath of air, millions of foreign bodies - dust particles, spores, airborne chemicals, viruses, bacteria - gain entry to the body. Anything the nose, adenoids, and tonsils cannot deal with passes into the lungs. Strange as it may seem, quiet breathing tends to be done through one side of the nose at a time, depending on the time of day.

To function properly the inside of the nose must be moist, warm, and sensitive. The nasal cavity, divided into two by a septum of cartilage and bone and guarded at its twin entrances by hairs, is lined with millions of blood capillaries and mucus-producing cells. Projecting into the top of the nasal cavity are more hairs, microscopic in size, which trap odour molecules and stimulate the endings of the olfactory nerve.

Paired sinuses - in the frontal, sphenoid, maxillary, and ethmoid bones of the skull - lead off the nasal cavity. Their function is to add resonance to the voice. Under normal circumstances they are air-filled but if their moist linings become irritated or inflamed by infections spreading from other parts of the upper respiratory tract, they fill with fluid, causing the whole area around the nose and eyes to feel tender and congested. Allergies can also cause blocked sinuses.

According to one theory, there are seven primary odour categories, each with its own kind of receptor in the nose; the brain mixes the information coming from the 50 million or so smell receptors in the nose and forms a smell picture. Though human beings are rather poor smellers in comparison with other animals, someone with a good sense of smell can recognize several thousand distinct smells. The olfactory lobe is connected to various structures on or near the lower surface of the forebrain, specifically to areas associated with memory and emotion. Smoking and any condition which causes a runny or blocked up nose impairs sensitivity to smells.

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Ailment & Diseases

  Disturbed Sense of Smell
  Hay Fever & Allergic Rhinitis
  Nasal Polyps

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