Describe how a faulty protein alters the movement of chloride ions across the cell membrane. How does this change in the cell membrane lead to the symptoms of cystic fibrosis?

CFTR protein facilitates the transport of chloride ions and water across the cells. Genetic defect in the CFTR gene results in defective protein synthesis. This defect in CFTR protein disrupts the chloride and water channel across the cell. The CFTR protein acts as a channel across the cell membranes which are specialized to produce mucus, sweat, tears etc. Failure of transport channel will result in symptoms like secretion of thick mucus. This mucus can obstruct the airflow and glands resulting in symptoms of cystic fibrosis.

CFTR (cystic fibrosis transmembrane conductance regulator) protein is necessary for transport of chloride ion across the cell membrane and chloride ion transport results in the movement of water in and out of the cell which results in dilution of mucus in tissues.

A mutation in the CFTR gene produces a faulty protein that is not able to transport chloride ions efficiently, therefore, the transport of water also hinders into the tissue which results in the thickening of mucus in lungs.

This thick mucus in lungs entraps bacteria and cause respiratory infection and also results in breathing problem which are the symptoms of cystic fibrosis.