Nostril

Human_Nostrils_01.JPG

External opening of the nose

Anatomy

A nostril (or naris; plural nares) is one of the two external openings of the nose, which are part of the respiratory system in humans and many other animals. The nostrils are involved in the process of respiration, allowing air to enter the nasal cavity and pass through the nasal passages to the lungs.

Anatomy

The nostrils are located on the nose and are separated by the nasal septum, a structure made of bone and cartilage. The outer edge of each nostril is called the ala of the nose. The nostrils are lined with a mucous membrane and tiny hairs called cilia, which help to filter out dust and other particles from the air.

Function

The primary function of the nostrils is to facilitate breathing by allowing air to enter the nasal cavity. The air is then warmed, moistened, and filtered before it reaches the lungs. The nostrils also play a role in the sense of smell by allowing odor molecules to reach the olfactory receptors in the nasal cavity.

Clinical significance

Nostril-related conditions can include nasal congestion, deviated septum, and nasal polyps. These conditions can affect breathing and the sense of smell. Treatments may involve medications, surgery, or other medical interventions.

Related structures

• Nasal cavity
• Nasal septum
• Sinus
• Olfactory system

See also

• Nose
• Respiratory system
• Olfactory system