Biological cells often possess thin, hair-like protrusions on their surface known as cilia, which serve various functions ...

To start, there are two kinds of nose hairs that are key here: the ones you can see and want to pluck, called the vibrissae, and the microscopic cilia, which are responsible for filtering mucus ...

Cilia are small hairs which beat to push the mucus back up the trachea so it can be swallowed and destroyed in the stomach. Clean air then enters the two bronchi, one bronchus going to each lung.