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ear

(Encyclopedia)CE5 Ear ear, organ of hearing and equilibrium. The human ear consists of outer, middle, and inner parts. The outer ear is the visible portion; it includes the skin-covered flap of cartilage known ...

Carnarvon, Henry Howard Molyneux Herbert, 4th earl of

(Encyclopedia)Carnarvon, Henry Howard Molyneux Herbert, 4th earl of, 1831–90, British statesman. As colonial secretary (1866–67) under the earl of Derby he introduced the British North America Act, which made C...

gene therapy

(Encyclopedia)gene therapy, the use of genes and the techniques of genetic engineering in the treatment of a genetic disorder or chronic disease. There are many techniques of gene therapy, all of them still in expe...

cork, in botany

(Encyclopedia)cork, protective, waterproof outer covering of the stems and roots of woody plants. Cork is a specialized secondary tissue produced by the cork cambium of the plant (see meristem, bark). The regularly...

hypertrophy

(Encyclopedia)hypertrophy hīpûrˈtrəfē [key], enlargement of a tissue or organ of the body resulting from an increase in the size of its cells. Such growth accompanies an increase in the functioning of the tiss...

chromosome

(Encyclopedia)chromosome krōˈməsōmˌ [key], structural carrier of hereditary characteristics, found in the nucleus of every cell and so named for its readiness to absorb dyes. The term chromosome is usually res...

cell, in biology

(Encyclopedia)CE5 Animal cell cell, in biology, the unit of structure and function of which all plants and animals are composed. The cell is the smallest unit in the living organism that is capable of integrati...

ammoniac

(Encyclopedia)ammoniac or gum ammoniac əmōˈnēăkˌ [key], yellowish substance with a sickening, bitter taste, obtained from the milky exudate of the injured stem of a plant (Dorema ammoniacum) found in Iran, In...

Brussels sprouts

(Encyclopedia)Brussels sprouts, variety (gemmifera) of cabbage producing small edible heads (sprouts) along the stem. It is cultivated like cabbage and was first developed in Belgium and France in the 18th cent. Br...

immunosuppressive drug

(Encyclopedia)immunosuppressive drug, any of a variety of substances used to prevent production of antibodies. They are commonly used to prevent rejection by a recipient's body of an organ transplanted from a donor...