The nose is the most protruding part of the face and is very important for facial recognition. The nose is also involved in olfaction or the sense of smell. The shape of the nose is determined by the nasal bones and the cartilage of the septum.
The nose has two nostrils, or external openings, that lead to the nasal cavity. The nasal cavity is divided into two cavities by the septum. The septum is a wall of bone and cartilage that separates the two cavities. Each cavity has a roof, a floor, and three walls. The roof and floor are made of bone, and the walls are made of cartilage.
The cavities are lined with a mucous membrane, which contains tiny hairs (cilia) that trap dust and other particles. The mucous membrane also produces mucus, which moistens the air we breathe and traps dust and other particles. Mucus also contains antibodies that help fight infection.
The nose thus has a major role in both respiration and smell. It also filters, warms, and humidifies the air we breathe.
The nose is also involved in speech. The sound of our voice is produced by the vibration of the vocal cords, which are located in the larynx (voice box). The air that passes through the larynx is shaped by the nose and mouth to produce speech.
The nose is a complex structure made up of bone, cartilage, and mucous membranes. It is an important part of the human face and body.