It helps our immunity system. It helps protect our lungs from different types of harmful agents. Now, once our air passes through the nasal cavity, it enters a region, a passageway known as our pharynx. And the pharynx is this connection between our esophagus and our larynx. Now, the larynx is essentially that section that connects to our passageway, the windpipe we call our trachea. And the larynx also contains our voice box that creates our voice.