nose

nose

[nohz]
nose, olfactory and respiratory organ, located between the eyes. The external nose, composed of bone and cartilage, is the most prominent feature of the face in humans. The internal nose is a hollow structure above the roof of the mouth, divided by the septum into two nasal cavities that extend from the nostrils to the pharynx. The mucous membrane that lines the nasal cavities is covered with fine hairs known as cilia that help to filter dust and impurities from the air before it reaches the lungs; the air is also moistened as it passes over the sticky nasal membrane. In the human nose, there are three horizontal folds on the walls of the nasal cavities, called the conchae: other mammals may have more conchae. The uppermost concha is densely supplied with capillaries that warm the air passing over them to near body temperature. High in the nasal cavity is a small tract of mucous membrane containing the nerve cell endings of the olfactory nerve, which impart the sense of smell. Therefore, inflammation of the nasal mucous membranes, which commonly accompanies colds and other infections, not only obstructs breathing but also impairs the sense of smell.

Prominent structure between and below the eyes. With the complex nasal cavity behind it, it functions for breathing and smelling. Behind the front section (vestibule), which includes the nostrils, it is divided vertically by three convoluted ridges (conchae) into air passages. In the highest one, the olfactory region, a small segment of mucous membrane lining contains neurons covered by a moisture layer, in which microscopic particles in inhaled air dissolve and stimulate the neurons. The rest of the cavity warms and moistens inhaled air and filters particles and bacteria out of it. Sinus cavities in the bone on both sides of the nose drain into the air passages. During swallowing, the soft palate closes off the back of the nose against food.

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Nose-jewels were only mentioned in the Bible in Isa. 3:21, although referred to in Gen. 24:47, Prov. 11:22, Hos. 2:13. They were among the most valued of ancient female ornaments. They "were made of ivory or metal, and occasionally jewelled. They were more than an inch in diameter, and hung upon the mouth. Eliezer gave one to Rebekah which was of gold and weighed half a shekel... At the present day the women in the country and in the desert wear these ornaments in one of the sides of the nostrils, which droop like the ears in consequence."

References

Nose rings, Nose studs are amongst the jewellery widely used in India and first found in India.

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