2.3 - How does CF affect other systems?

Question 1

How does CF affect the digestive system?

Answer 1

• Pancreatic duct blocked by mucus
• Digestive enzymes not released
• Lowered rate of digestion
• Energy is lost as incomplete digestion

Question 2

What problems does CF cause for the pancreas?

Answer 2

• Pancreatic enzymes become trapped
• Cysts of hard, damaged tissue in pancreas
• Damage to insulin producing cells
• Can cause diabetes

Question 3

Describe lock and key theory

Answer 3

• Substrate molecules form temporary bonds with amino acids of active site to produce enzyme substrate complex
• Each enzyme catalyses only one reaction as only one precise substrate fits to active site

Question 4

Describe induced fit theory

Answer 4

• When substrate enters active site, enzyme changes shape to fit more tightly around substrate
• The slight change in shape encourages reaction

Question 5

What is activation energy?

Answer 5

• Breaking bonds requires energy

- The energy must be gained from somewhere, often heat

Question 6

How do enzymes reduce activation energy?

Answer 6

• Shape of the enzyme substrate complex means charged groups interact
• Attraction of charged groups distorts shapes to assist in breaking or making bonds
• In some cases, side chains on amino acids may provide acidic conditions for the reaction

Question 7

How does CF affect female reproduction?

Answer 7

• Mucus plug develops in the cervix

- Stops sperm from fertilising egg

Question 8

How does CF affect male reproduction?

Answer 8

• Lack the vas deferens (sperm duct)
• Sperm cannot leave testes
• Sperm duct can be blocked by mucus
• Lower sperm count