When to see a doctor. See a doctor if you or a loved one has memory problems or other dementia symptoms. Some treatable medical conditions can cause dementia symptoms, so it's important to determine the underlying cause.
A brief history of tobacco. (CNN) -- Tobacco was first used by the peoples of the pre-Columbian Americas. Native Americans apparently cultivated the plant and smoked it in pipes for medicinal and ceremonial purposes.
There are several varieties of tobacco. Nicotiana tabacum, or common tobacco, is the primary source of tobacco in cigarette manufacturing. Nutrients are contained in foods or found in the ambient natural environment. These nutrients serve as food for plants, promoting their growth and development.hemical. A chemical is a combination of atoms. For example, nicotine, a chemical naturally present in the tobacco plant and responsible for tobacco addiction, is composed of carbon (10), hydrogen (14) and nitrogen (2) atoms.