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influenza

(Encyclopedia)influenza or flu, acute, highly contagious disease caused by a RNA virus (family Orthomyxoviridae); formerly known as the grippe. There are three types of the virus, designated A, B, and C, but only t...

abortion

(Encyclopedia)abortion, expulsion of the products of conception before the embryo or fetus is viable. Any interruption of human pregnancy prior to the 28th week is known as abortion. The term spontaneous abortion, ...

stem cells

(Encyclopedia)stem cells, unspecialized human or animal cells that can produce mature specialized body cells and at the same time replicate themselves. Embryonic stem cells are derived from a blastocyst (the blastu...

smoking

(Encyclopedia)smoking, inhalation and exhalation of the fumes of burning tobacco in cigars and cigarettes and pipes; in the 21st cent., vaping, the similar use of e-cigarettes, also has become common. Some persons ...

blood

(Encyclopedia)blood, fluid pumped by the heart that circulates throughout the body via the arteries, veins, and capillaries (see circulatory system; heart). An adult male of average size normally has about 6 quarts...

rice

(Encyclopedia)rice, cereal grain (Oryza sativa) of the grass family (Graminae), probably native to the deltas of the great Asian rivers—the Ganges, the Chang (Yangtze), and the Tigris and Euphrates. The plant is ...

cotton

(Encyclopedia)cotton, most important of the vegetable fibers, and the plant from which the fiber is harvested. Today the leading cotton states are Texas, Georgia, Mississippi, Arkansas, North Carolina, and Louisi...

circulatory system

(Encyclopedia)CE5 Circulatory system circulatory system, group of organs that transport blood and the substances it carries to and from all parts of the body. The circulatory system can be considered as compose...

Amazon, river, Peru and Brazil

(Encyclopedia)Amazon, Port. Amazonas ämäzōˈnəs [key], world's second longest river, c.3,900 mi (6,280 km) long, formed by the junction in N Peru's Andes Mts. of two major headstreams, the Ucayali and the short...

food poisoning

(Encyclopedia)food poisoning, acute illness following the eating of foods contaminated by bacteria, bacterial toxins, natural poisons, or harmful chemical substances. It was once customary to classify all such illn...