Final answer:
Cystic fibrosis is a genetic disease causing thick mucus buildup mainly in the lungs and pancreas, leading to respiratory infections and malabsorption of nutrients. Due to medical advances, the life expectancy of patients with cystic fibrosis has increased significantly.
Step-by-step explanation:
Cystic fibrosis is a common autosomal recessive genetic disease that causes the production of thick mucus that predominantly clogs the respiratory and digestive systems. This disease is the result of a mutation in a gene called CFTR, which leads to a defective protein responsible for the movement of sodium chloride into and out of cells.
Consequently, the mucus in patients with cystic fibrosis is abnormally thick and sticky, causing frequent lung infections due to bacterial colonization and malabsorption of nutrients because of digestive tract blockages.
Historically, individuals with cystic fibrosis had a very short life expectancy, rarely living over 10 years. Today, thanks to advances in medicine, people with cystic fibrosis can live into middle adulthood. The lungs and pancreas are primarily affected, with the thick mucus leading to breathing difficulties and chronic lung infections, as well as obstructing the function of the pancreas.