Your lungs are made up of many parts that work together to help you breathe.
Each lung is divided into sections called lobes.
When you inhale (or breathe in), air enters the trachea (windpipe). It then travels through smaller airways (the bronchi and bronchioles) to tiny air sacs deep within the lungs (the alveoli).
In the alveoli, oxygen passes into your bloodstream from the air you breathe in. At the same time, carbon dioxide passes from the bloodstream into the air you exhale (or breathe out).
How CF Affects the Lungs
The airways in your lungs contain a layer of mucous—a protective coating that is constantly produced by lung cells.
Humans have a gene for making a protein called CFTR. People with CF have abnormal copies of this gene. It is thought that these abnormal genes result in dehydrated mucous that cannot easily be cleared from the lungs.
Thick stationary mucous obstructs, or blocks, airways (making it difficult to breathe) and gives infection-causing bacteria a place to grow.
