As we'll see in just a moment, there's a special type of skeletal muscle known as our diaphragm. And the diaphragm separates our lungs from the stomach and the small intestine, and it also functions in the process of respiration. Now, let's actually discuss the way that our air moves into our lungs via this passageway system that we have that connects between our nose and our lungs. So essentially, when we breathe in we can either breathe in through our mouth, or we normally breathe in through our nose. Now, when we breathe in through our nose, the air, and this includes things like nitrogen oxygen that moves in to our nasal cavity, the nasal cavity, or the canals found within our nose. Now, the lining of the nasal cavity consists of a special type of slimy and sticky membrane known as the mucous membrane.