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genetic engineering

(Encyclopedia)CE5 Genetic engineering: Gene-splicing techniques genetic engineering, the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biologica...

food preservation

(Encyclopedia)food preservation, methods of preparing food so that it can be stored for future use. Because most foods remain edible for only a brief period of time, people since the earliest ages have experimented...

cactus

(Encyclopedia)cactus, any plant of the family Cactaceae, a large group of succulents found almost entirely in the New World. A cactus plant is conspicuous for its fleshy green stem, which performs the functions of ...

social work

(Encyclopedia)social work, organized effort to help individuals and families to adjust themselves to the community, as well as to adapt the community to the needs of such persons and families. Social work emerge...

poliomyelitis

(Encyclopedia)poliomyelitis pōˌlēōmīˌəlīˈtĭs [key], polio, or infantile paralysis, acute viral infection, mainly of children but also affecting older persons. Historically, there were three immunologic ty...

obesity

(Encyclopedia)obesity, condition resulting from excessive storage of fat in the body. Obesity is now usually defined using a formula known as the body mass index (BMI), in which weight (in kilograms) is divided by ...

acupuncture

(Encyclopedia)CE5 Acupuncture points for treating diseases of the large intestine. acupuncture ăkˈyo͝opŭngˌchər [key], technique of traditional Chinese medicine, in which a number of very fine metal needl...

bacteria

(Encyclopedia)bacteria [pl. of bacterium], microscopic unicellular prokaryotic organisms characterized by the lack of a membrane-bound nucleus and membrane-bound organelles. Once considered a part of the plant king...

Gibraltar

(Encyclopedia)Gibraltar jĭbrôlˈtər [key], British overseas territory (2015 est. pop. 34,000), 2.5 sq mi (6.5 sq km), on a narrow, rocky peninsula extending into the Mediterranean Sea from SW Spain. Most of the ...

malaria

(Encyclopedia)malaria, infectious parasitic disease that can be either acute or chronic and is frequently recurrent. Malaria is common in Africa, Central and South America, the Mediterranean countries, Asia, and ma...