Structure of Nose

The human nose is a complex structure. It can be broadly divided into two segments: external nose and internal nose. The details of the structure of the nose are discussed below:

External Structure of Nose

The external nose is the visible part of the nose on the face and comprises various structures. These structures include:

1. Tip: It is the pointed end of the nose.
2. Nostrils or the Nares: These are the two openings at the base of the nose through which air enters.
3. Alae: These are the wing-like structures on either side of the nostrils. The alae are made up of cartilage and soft tissue.
4. Nasal Bridge: This is the bony upper part of the nose that extends between the eyes.
5. Nasal Septum: This is the dividing wall between the nostrils. The anterior part of the septum is made up of cartilage whereas the posterior end is made up of bone.
6. Columella: It is a small strip of skin that separates the nostrils at the base of the nose.

Innervation and Blood supply: A branch of the trigeminal nerve provides sensory innervation to the skin of the external nose and blood supply is maintained by the branches of the facial artery that arise from the carotid artery.

Internal Structure of Nose

The internal structure of the nose includes the large empty cavity called nasal cavity. This cavity is divide into section by the nasal septum. The lateral walls of the nasal cavity have three bony projections called nasal conchae or turbinates that increase the surface area of the nasal cavity and help humidify, filter, and warm the inhaled air. There are spaces between the nasal conchaes that directs the flow of air. These spaces are called nasal meastuses.

• The anterior part of the nasal cavity is called the nasal vestibule. This region is lined with skin containg hair follicles and sebaceous glands. On moving up into the nasal cavity we encounter the region that contains olfactory cells which are specialised for the sense of smell.
• The nasal cavity continues to connect with hollow cavities called paranasal sinuses. There are four pairs of paranasal sinuses that produces mucus and maintain the resonance of sound. A duct called nasolacrimal duct unites with the tear duct that allows the flow of tears into the nose.

Innervation and blood supply: The branches of trigeminal nerve and olfactory nerve inervates the internal nose. Blood supply is maintained by different facial arteries.

The structure of the nose is a complex design composed of bones, cartilage, and soft tissue. The external structure of the nose is somewhat triangular and is primarily shaped by two bones. The internal structure includes a cavity lined by mucus membrane and hair follicles that keep away foreign particles and humidify the inhaled air.

The nasal cavity is divided by a nasal septum. At the base of the nasal cavity lie the two nostrils that act as an entry to the nose. The nose is mainly innervated by the branches of the trigeminal nerve and olfactory nerve. Blood supply to both the external and internal nose is taken care of by various facial arteries that branch out from the carotids.