14. Asthma causes _____________ of the airways. 15. Smoking is a _____________ factor that affects the respiratory system. 16. Cigarette smoke contains chemicals that cause _____________ in the mouth, lungs and other body organs.
17. Smoking is the _____________ cause of lung cancer. K U
Knowledge and Understanding 1. Outline the function of the following structures in the respiratory system: (a) Hairs in the nose. (b) Dense blood supply in the nose. (c) Cartilage in the trachea. (d) Moist alveoli. (e) Ribs surrounding the lungs.
2. Describe how the respiratory system prevents food from going into the airways. 3. Draw a diagram of the respiratory system, using arrows to show where the air goes when you breathe in.
T I
Thinking and Investigating 1. Below is a diagram of an alveolus in the lungs.
(a) Describe what is happening at: A, B, C, D, E and F. (b) Smoking can lead to a build-up of tar in the alveoli. What effect do you think this has on the person? Explain your answer.
(c) Explain how a cracked rib might affect your breathing. (d) On a cold day how would the air breathed in through your nose differ from the air breathed in through your mouth?
