Respiration

Question 1

Components of cigarettes + Effects

Answer 1

1. Tar
   - Uncontrolled division of cells, increased risk of lung cancer
   - Increased risk of chronic bronchitis, leading to emphysema
   ——
2. Nicotine
   - Increased heart rate & blood pressure
   - Increased risk of blood clots, which increases risk of CHD
   - Increased rate of fatty deposits on inner wall of arteries , narrowing arteries
   ——
3. CO
   - Binds irreversibly to haemoglobin in RBCs to form carboxyhaemoglobin
   -> Redices ability of RBCs to transport O2
   - Increases risk of CHD as less O2 is transported to lungs

Question 2

Diseases from Smoking

Answer 2

1. Chronic bronchitis
   - Tar causes inflammation of gland cells in trachea
   -> l excessive mucus produced
   -> Cilia in trachea paralysed, can’t sweep mucus containing trapped foreign particles up to nose to be removed
   -> Smoker must manually cough up mucus, which leads to emphysema
   ———
2. Emphysema
   - Persistent and violent coughing
   - Breakdown of partition walls of alveoli
   - Lower SA to Vol ratio of alveoli in contact with air for gaseous exchange
   - Lungs lose elasticity & breathing more difficult
   ———
3. Lung cancer by tar