Cystic Fibrosis

Question 1

What does the CFTR gene do normally

Answer 1

Codes for channel proteins in the cell membrane that transport chloride ions out of cells of respiratory tract and into the mucus meaning water enters the mucus due to osmosis as higher solute concentration in mucus than cells making mucus less sticky and thick

Question 2

What mutation causes CF and what does this do

Answer 2

-mutation in the CFTR gene making it less efficient at transporting chloride ions. This makes the mucus very thick

Question 3

How CF affects the respiratory system

Answer 3

-build up of mucus in lungs traps bacteria which increases risk of infection
-build up in airways decreases SA of alveoli which decreases SA for gas exchange and increases diffusion distance

Question 4

How does CF affect reproductive system in females

Answer 4

Cervical mucus prevents sperm from reaching the egg

Question 5

How does cf affect reproductive system in males

Answer 5

Sperm ducts can become blocked with mucus meaning sperm produced cannot leave the testes

Question 6

How does cf affect the digestive system

Answer 6

-pancreatic duct can become blocked with mucus meaning digestive enzymes do not reach the small intestine and food is not properly digested so absorb fewer nutrients
-mucus can cause cysts to form in pancreas which damages insulin producing cells and can lead to diabetes