How does human take in air?

Air goes into the lungs and inflates tiny airsacs called alveoli. It is then pushed out by a muscle called the diaphragm. while in the alveoli, the oxygen in the air is exchanged for carbon dioxide....

It is officially known as the trachea.

air sacs are in the lungs and when you breathe in blood carries it to the lungs.

it depends on if a person had a illness or not

Oxygen