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Tobacco: Nicotine
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Tobacco smoking is the inhalation of smoke from burned dried or cured leaves of the tobacco plant. People smoke for pleasure, for ritualistic or social purposes, or for self-medication,[1] as well as to satisfy a physiological dependence on nicotine. Tobacco use by Native Americans throughout North and South America dates back to 2000BC. The practice was brought back to Europe by the crew of Christopher Columbus. Tobacco smoking took hold in Spain and was introduced to the rest of the world, via trade. Tobacco is an agricultural product processed from the fresh leaves of plants in the genus Nicotiana.
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Tobacco is not a homogeneous product. The flavor, mildness, texture, tar, nicotine, and sugar content vary considerably across varieties or types of tobacco. Defining characteristics of different tobacco types include the curing process (flue-, air-, sun-cured) and leaf color (light or dark), size, and thickness. A given type of tobacco has a different quality depending on where it is grown, its position on the stalk (leaves near the bottom of the stalk are lower in quality), and weather conditions during growing and curing.4
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Tobacco contains nicotine, an addictive drug. Tobacco smoke ... contains more than 4,000 chemical compounds, including at least 43 cancer-causing compounds. Forms of tobacco that are smoked—cigarettes, pipes, and cigars—cause lung cancer, emphysema, and other respiratory diseases. Smoking also contributes to coronary heart disease and, in pregnant women who smoke, low birth weight of newborns. Chewing tobacco and inhaling snuff causes cancer of the mouth, nose, and throat and can lead to nicotine addiction.
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Tobacco contains a variety of different poisonous substances, but the dangers of three of them are particularly important. Nicotine is the substance that causes addiction to tobacco. It acts as a tranquilizer, but ... stimulates the release of epinephrine into the smoker's bloodstream that elevates his/her blood pressure. Carbon monoxide passes from the lungs into the bloodstream, where in competition with oxygen, is easily combines with hemoglobin and thus interferes with the oxygenation of tissues. In the long term, persistently high levels of carbon monoxide in the blood of the smokers will lead to hardening of the arteries, which increases the risk of coronary thrombosis. Tar in tobacco produces chronic irritation of the respiratory system and is the major cause of lung cancer
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Tobacco smoke contains nicotine and harmane (a MAO inhibitor), which combined give rise to addictive stimulant and euphoriant properties. The effect of nicotine in first time or irregular users is an increase in alertness and memory, and mild euphoria. Nicotine ... disturbs metabolism and suppresses appetite. This is because nicotine, like many stimulants, increases blood sugar.
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Tobacco plants engineered with 22nd Century's technology are capable of delivering various nicotine levels--from virtually none to greater than twice the levels of conventional tobacco varieties presently used in commercial cigarettes. New and autonomous plant lines can be created with even small incremental variations in their respective nicotine contents. These new cultivars will facilitate and expedite advanced tobacco breeding, better tobacco blending, new product development, and cigarette product testing.
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