COPD, or Chronic Obstructive Pulmonary Disease, pretty much says it all. In COPD the Bronchioles (the pathways of air to the Aveoli), become inflamed and are occluded by mucus, because the Cilia which are responsible for pushing it out of the tract have been damaged. Because of the narrowing, the Aveoli attempt to increase the surface area so that more oxygen can be absorbed by the lungs, however this can lead to a problem as the dead space (space that is not the aveoli and can be absorbed) is then expanded as well, which leads to shortness of breath.
The answer is the epiglottis
