Nose

Nose, organ of breathing and smell, located in the middle of the face. The nose consists of bone and cartilage extension with 2 external openings, or nostrils. These pass into the nasal cavities, which are separated from each other by a septum and contain turbinates that increase the mucous membrane surface and direct the air flow. The chemoreceptors for smell lie mainly in the roof of the nasal cavities, but fine nerve fibers throughout the nose contribute both to tactile sensation and smell.