Final answer:
The CFTR protein is a membrane ion channel that transports chloride ions in and out of cells. Mutations in the CFTR gene can result in the production of a defective CFTR protein. This malfunctioning CFTR protein leads to the symptoms of cystic fibrosis, primarily affecting the lungs.
Step-by-step explanation:
The CFTR protein, also known as the cystic fibrosis transmembrane conductance regulator, is a membrane ion channel that transports chloride ions out of the cell. In a person with cystic fibrosis (CF), the gene for CFTR is mutated, resulting in the production of a defective channel protein.
This defective CFTR protein is not properly incorporated into the cell membrane and is instead degraded by the cell. The malfunctioning CFTR protein leads to the symptoms of CF, which primarily affect the lungs but can also affect other organs.