nostril

anatomy

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Last updated

July 1, 2026

Quick Summary

The nostril is the external opening of the nasal cavity, which is part of the olfactory system responsible for the sense of smell. While paired nostrils might seem redundant, each nostril can prioritize either breathing or smelling at different times. One nostril may draw in more air for breathing, while the other, with less airflow, is better at detecting certain scents.123

The nasal cavity itself is complex, lined with mucous membranes that filter, warm, and moisten inhaled air. This lining contains olfactory receptors that detect odor-emitting substances dissolved in moisture. The nose also serves as an entrance to the respiratory tract, conditioning air before it reaches the lungs.24

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nose
…are known as nares or nostrils. The roof of the mouth and the floor of the nose are formed by the palatine bone, the mouth part of which is commonly called the hard palate; a flap of tissue, the soft palate, extends back into the nasopharynx, the nasal portion of…
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…are known as nares or nostrils. The roof of the mouth and the floor of the nose are formed by the palatine bone, the mouth part of which is commonly called the hard palate; a flap of tissue, the soft palate, extends back into the nasopharynx, the nasal portion of…
Read More

Why Do Our Noses Have Two Nostrils?
The reason for paired nostrils, however, is a little less obvious. While there is no such thing as stereo olfaction (smelling), the pairing of our nostrils is not just for show.
Read More
The reason for paired nostrils, however, is a little less obvious. While there is no such thing as stereo olfaction (smelling), the pairing of our nostrils is not just for show.
Read More