1. Gas exchange in the alveoli The alveoli are bunches of tiny air sacks inside the lungs. Each individual sack is called an alveolus. They are located at the end of the bronchioles. When you breathe in, they fill with air. The alveoli are covered in tiny blood vessels called capillaries. The capillaries are very thin (one cell thick) so O 2 and CO 2 can pass through each alveolus into the blood stream. Word list: capillaries blood bronchioles alveolus alveoli

2. How does smoking affect the lungs? Which picture shows the healthy lungs of a non-smoker and which show the unhealthy lungs of a smoker? healthy lungssmoker’s lungs Not a difficult question to answer but some people still think that smoking is cool!

3. How does smoking affect health? Effects of smoking on health bronchitis liver cancer osteoporosis mouth, lip and throat cancer asthma lung cancer dental hygiene problems facial wrinkles pancreatic cancer impaired immune system heart disease cervical cancer kidney cancer sperm abnormalities and impotence bladder cancer leukaemia emphysema stomach cancer testicular cancer menstrual problems

4. Asthma

5. Emphysema Caused by exposure to toxic chemicals or long- term exposure to tobacco smoke.

6. Emphysema