Science 8th grade
UNIT 4: Respiration 4.5 Cigarettes and health
Science 8th grade
UNIT 4: Respiration 4.5 Cigarettes and health
One of the easiest ways to make yourself unfit, and to make your lungs and heart work less well, is to smoke cigarettes.
The World Health Organization estimates that each year.
• 4/2 million people will die early as a result of smoking cigarettes.
• cigarettes kill half of all the people who smoke them regularly
• smoking kills more people each year than all the deaths from HIV/AIDS, drugs and road accidents added together.
People who do not smoke cigarettes themselves may get ill if they breathe in other people's cigarette smoke. Children are especially at risk, if adults in their home regularly smoke cigarettes.
What is in cigarette smoke?
Nicotine
Nicotine is a drug. A drug is a substance that changes the way the body works. Some drugs-for example, aspirin and antibiotics - are useful. However, nicotine is a harmful drug.
Nicotine is addictive. This means that, once your body has got used to it, it is very difficult to stop taking it.
Nicotine makes blood vessels get narrower, so the heart has to work harder to push blood through them. Smokers are much more likely to develop heart disease than non-smokers.
Tar
Tar in cigarette smoke causes cancer Cancer is a disease in which some cells divide uncontrollably, forming a lump called a tumour. Many cancers can now be treated, but it is still very difficult to treat cancer in the lungs. Smoking cigarettes increases the risk of developing all types of cancer, but especially lung cancer.
Carbon monoxide
Carbon monoxide is an invisible gas. It combines with the haemoglobin inside red blood cells. This means that they cannot carry as much oxygen.
Particulates
Particulates are tiny particles of soot and other They get into the lungs and damage the cells. The thin walls of the air sacs may break down. This makes it much more difficult for oxygen to get from the air sacs into the blood.
Questions
1) Explain why smokers find it very hard to give up smoking.
$A+I$: 2) Some people smoke low-lar cigarettes. Discuss whether or not this is a good idea.
3) Compare the appearance of the lung tissue in the two photographs on the previous page.
$A+I$: 4) Most professional sportsmen and sportswomen do not smoke. Explain why.
Activity 4-5 (Smoking questionnaire)
Construct a questionnaire to investigate one or more questions about smoking.
For example, you could try to find out:
• why people have chosen to smoke or not to smoke
• what people know about the ways in which cigarettes affect health.
People are more likely to answer your questionnaire if it is quite short and easy to complete.
Show your questionnaire to your teacher before you try it out. Your teacher will give you guidance about how you can use it.