1. Smoking
IGCSE Science

2. Learning objectives List the substances found in cigarette smoke
Outline the effects of smoking on the respiratory system
Discuss the effects of smoking during pregnancy

4. The main three things….
Nicotine. Nicotine is the addictive substance in tobacco. ...
Carbon monoxide. Carbon monoxide combines with the haemoglobin in red blood cells and so reduces the ability of the blood to carry oxygen. ...
Tars. This consists of a thick liquid that collects in the lungs. Some of these cause cancer.

5. The effects….
Effects of smoking on the respiratory system. The effects of tobacco smoke on the respiratory system include: irritation of the trachea (windpipe) and larynx (voice box) reduced lung function and breathlessness due to swelling and narrowing of the lung airways and excess mucus in the lung passages.

6. The effects….
The build-up of thick mucus and the inability of the cilia to move it leads to a SMOKER’S COUGH.
Frequent coughing over many years leads to further damage….

7. The Effects….
Smoker’s cough causes damage to the delicate walls of the air sacs/alveoli.
This means that there is less surface area for GASEOUS EXCHANGE.
The damage to the alveoli is known as EMPHYSEMA.