Cystic Fibrosis

Question 1

What’s CF?

Answer 1

Inherited disorder that affects respiratory digestive and reproductive systems
It is caused by 2 recessive alleles but if the person has 1 recessive allele they are a carrier of the disease
MUST INHERIT 1 RECESSIVE ALLELE FROM EACH PARENT

Question 2

What does CF cause/produce?

Answer 2

Thick sticky mucus

Question 3

What’s the mutation in the gene causing CF called?

Answer 3

CFTR (cystic fibrosis transmembrane conductance regulator)

Question 4

What type of protein is CFTR?

Answer 4

Channel protein

Question 5

What does CFTR do to cause sticky mucus?

Answer 5

Less efficient at transporting sticky chloride ions out of cell so less water moves out via osmosis therefore making mucus sticky and thick

Question 6

How does CF affect the respiratory system?

Answer 6

Cilia unable to move mucus towards throat due to the thickness
Mucus builds up in airways
They can become block and gas exchange cannot take place
Surface area for gas exchange is reduced causing breathing difficulties

Question 7

How does CF affect digestive system?

Answer 7

Tube connecting pancreas to small intestine can become blocked - preventing digestive enzymes produced by pancreas from reaching small intestine reducing ability to digest food
Mucus can chase cycle to grow in pancreas that inhibit production of enzymes reducing ability to digest food
Lining of small intestine is thick with mucus

Question 8

How does CF affect the reproductive system?

Answer 8

Tubes connecting testicles to penis are absent and can be blocked by mucus so sperm cannot reach penis
Thickened cervical mucus can prevent sperm reaching egg due to mucus reducing the mobility of sperm