Question

Why does a person with Cystic Fibrosis have sticky mucus on the airway of their lungs instead of thin mucus like healthy individuals?

a) Overproduction of mucus
b) Lack of mucus production
c) Abnormal ion transport
d) Presence of excess water in the mucus

Answer 1

Cystic Fibrosis causes thick, sticky mucus due to abnormal ion transport resulting from defective CFTR protein, which affects the water concentration gradient in mucus.

Step-by-step explanation:

A person with Cystic Fibrosis (CF) has sticky mucus on the airways of their lungs due to abnormal ion transport caused by a malfunction in the cystic fibrosis transmembrane conductance regulator (CFTR). The CFTR is a protein responsible for transporting Cl- ions out of cells. In CF, a mutation in the CFTR gene leads to defective channel proteins. This defect prevents Cl- ions from being properly transported out of the cells, which in turn inhibits the establishment of a normal water concentration gradient, resulting in no osmotic pressure to pull water into the mucus. As a consequence, the mucus becomes thick and sticky, obstructing airways and making it difficult for the ciliated epithelia to clear it, leading to increased susceptibility to lung infections and other issues.