And the pharynx basically is the connection point between the esophagus, our mouth, as well as our larynx. So the cilia can move the pathogens along our trachea. And ultimately, those pathogens end up in our pharynx. And then those pathogens either can be swallowed through our esophagus and end up in our highly acidic and highly deadly environment inside our stomach which can ultimately kill off that pathogen or we can expel that pathogen or harmful substance via the process of spitting. Now, inside the nasal cavity, we also have actual tiny hairs. And what these hairs actually do is they can help trap our dust particles and other particles inside the nasal cavity before it actually goes into our lungs.