Final answer:
The dysfunction of CFTR hinders chloride ion transport, impairing the hydration of mucus and causing complications in multiple organs, characteristic of cystic fibrosis.
Step-by-step explanation:
Cystic fibrosis (CF) is a genetic autosomal recessive disease characterized by the production of thick, sticky mucus that clogs the respiratory and digestive systems, primarily due to the malfunction of an ion channel protein known as cystic fibrosis transmembrane conductance regulator (CFTR). In individuals with CF, the CFTR gene is mutated, resulting in a defective channel protein that is often not incorporated into the cell membrane but instead degraded by the cell. This defective protein is supposed to transport Cl- ions out of cells, but when absent or malfunctioning, it leads to inadequate Cl- ion transport. Consequently, the failure to move these ions causes the lack of a normal water concentration gradient and osmotic pressure, which should normally draw water into the mucus and keep it thin and flowing. The result is the production of abnormally thick mucus which cannot be effectively cleared by the ciliated epithelia, leading to blockage of air and mucus flow, frequent lung infections, and other issues related to malabsorption of nutrients.