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
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