The trachea divides into two tubes called the bronchi. The bronchi divides into many tubes called bronchioles. The bronchioles divide until they end up in tiny air sacs called alveoli. There are ...

To understand COPD’s pathophysiology, it’s important to understand the structure of the lungs and how they work: When you inhale, air moves down your trachea and then through two tubes called ...

After air goes in your trachea, it travels through your bronchi to your lungs, then passes into progressively smaller tubes called bronchioles. It eventually reaches alveoli, super-small air sacs ...