Humans have a total of four nostrils.
While it's commonly thought that humans only have two nostrils, that's only partially true. Here's a breakdown:
External Nostrils (Anterior Nares)
- These are the two openings that are visible on the nose.
- These are often referred to as simply "nostrils".
- Air enters the nasal cavity through these openings.
Internal Nostrils (Posterior Nares, Choanae)
- In addition to the two external nostrils, humans also have two internal nostrils located at the back of the nasal cavity.
- These are also called posterior nares, posterior nasal apertures, or choanae.
- Air passes through the internal nostrils into the pharynx (throat) after being conditioned within the nasal cavity.
The nasal cavity serves to warm, moisten, and filter the air before it reaches the lungs. Understanding the dual openings – two external and two internal – highlights the complex pathway of air during breathing. This anatomical design allows for efficient respiration.
| Nostril Type | Number | Location | Function |
|---|---|---|---|
| External Nostrils | 2 | Visible openings on the nose | Air entry into the nasal cavity |
| Internal Nostrils | 2 | Back of the nasal cavity, inside the head | Air passage from nasal cavity to pharynx, part of the respiratory tract |
Therefore, while we see only two nostrils externally, there are indeed a total of four nostrils involved in human respiration, two in the front and two further back in the nasal cavity.
