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Tar
In I/GCSE biology,
- Tar is the name to describe the chemical substances in cigarettes, and is the most harmful substance in a tobacco cigarette.
- It is tar that makes your fingernails, teeth and skin go yellow.
- The cilia that line your trachea and bronchus try to trap the tar from the cigarette, as their job is to trap dirt. When they try to trap the tar, instead the tar covers them and stops them working effectively, and will eventually kill them. Now they can’t work, you can catch really nasty illnesses.
- Emphysema is one of those really horrible diseases. When you inhale, the lungs expand and then pulled back to their original state by their elastic tissues. When you have emphasyma, these elastic tissues get damaged because of the tar deposits, and so the lungs aren’t as elastic. The result of this is that you can’t get as much diffusion from a breath.
- Other illnesses include cancer of the lungs and throat.
Pregnancies
- Cigarette smoke contains drugs and poisons which can cause serious health problems for the mother and child.
- According to I/GCSE biology curriculum, problems for the baby include;
- Can be up to 200g lighter
- Cot death is 3 x more likely
- Poorer lung function and poorer respiratory problems
- 3 x more likely to die within a week
- Malnutrition from poor milk production
- Lower oxygen levels in the blood
- Higher infant mortality rate
- Less immunity to flu and diarrhoea
- More likely to become smokers when older.
- Problems for the mother include;
- Higher risk of miscarriage
- Reduces fertility
- During labour, complications like premature detachment of the placenta and the membranes rupturing can occur as well as bleeding. Ectopic pregnancy is more common too. During the pregnancy, a baby depends on the placenta, and umbilical cord for transferring vital nutrients and oxygen; if these organs are damaged, the baby can be at risk in I/GCSE biology.
End of this topic!
