CF

Question 1

How does CF effect the gas exchange system?

Answer 1

Thick mucus blocks the narrow airways in the bronchioles preventing movement of air into the alveoli
• Reduces the number of alveoli providing surface area
• Blockages allow air to pass when the person breathes in but not out resulting in over inflation of lung tissue damaging elasticity of lungs.
• Gas exchange cannot deliver enough oxygen to their muscle cells – needed for respiration
• Short of breath when exercising

Question 2

How does CF affect the digestive system?

Answer 2

Mucus lining in the small intestine is abnormally thick which inhibits absorption of nutrients
• The pancreatic duct is blocked preventing digestive enzymes produced by the pancreas from reaching the small intestine making digestion harder.
• Food is not fully digested therefore not all nutrients is absorbed so faeces contain high proportion of undigested food, lose energy.
• Difficult to maintain body mass
• High basal metabolic rates

Question 3

How does CF affect the reproductive system?

Answer 3

• Reduces fertilisation rates
• Mucus plug develops in the cervix stopping sperm from reaching the egg
• Lack sperm duct on both sides so sperm cannot leave the testes
• When sperm duct is present it can become partially blocked by mucus

Question 4

Sweat

Answer 4

CFTR and ENaC proteins allow reabsorption of NaCl from sweat as it moves to skin surface
Sweat released and evaporates