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Tobacco Essay Research Paper Tobacco comes from

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Tobacco Essay, Research Paper

Tobacco comes from the tobacco plant, nicotiana

tobacum. Leaves of the plant may be smoked, inhaled in

form of snuff, or chewed. Tobacco smoke contains about

4000 chemicals. Many of them (nicotine, tar, and carbon

monoxide) are very harmful. Effects of Smoking Nicotine is

a stimulant (substance that speeds up body activities) which

increases the heartbeat and raises blood pressure. Nicotine

causes the arteries to narrow, which places stress on the

circulatory system. Cigarette smoke contains many tiny

particles. When they form a sticky brown substance called

tobacco tar. Tar builds up in the lungs of a smoker. Carbon

Monoxide is a poisonous gas in cigarette smoke. When

inhaled, it replaces some of the oxygen that is carried by

red blood cells. This makes the heart work harder.

Smoking and the Circulatory System Smokers are most

likely to die of heart disease. Smoking is linked to the

formation of blood clots in the arteries. If blood supply to

heart is interrupted, a stroke occurs. Smoking and The

Respiratory System Smoking slows the cilia (tiny hair-like

projections) in the nasal passages down. Poisonous

substances are then able to spread over the linings of the air

passages. Smokers are more prone to the following upper

respiratory problems: -Colds -Pneumonia -Chronic

Bronchitis -Emphysema -Lung Cancer -Cancer of the

Mouth, Larynx and Esophagus, Bladder, and Kidneys