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ozone layer

(Encyclopedia)ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone, located at altitudes of 12–30 mi (19–48 km) above the earth's surface. Ozone in the ozone...

cheese

(Encyclopedia)cheese, food known from ancient times and consisting of the curd of milk separated from the whey. The numerous cheeses (often named for their place of origin) depend for their distinctive qualities ...

cholesterol

(Encyclopedia)CE5 cholesterol kəlĕsˈtərōlˌ [key], fatty lipid found in the body tissues and blood plasma of vertebrates; it is only sparingly soluble in water, but much more soluble in some organic solvent...

menopause

(Encyclopedia)menopause klīmăkˈtərĭk, klīˌmăktĕrˈĭk [key], transitional phase in a woman's life when the ovaries stop releasing eggs, ovarian production of estrogen and other hormones tapers off, and men...

mustard

(Encyclopedia)CE5 Black mustard, Brassica nigra mustard, common name for the Cruciferae, or Brassicaceae, a large family chiefly of herbs of north temperate regions. The easily distinguished flowers of the Cruc...

milk, food

(Encyclopedia)milk, liquid secreted by the mammary glands of female mammals as food for their young. The milk of the cow is most widely used by humans, but the milk of the mare, goat, ewe, buffalo, camel, ass, zebr...

seaweed

(Encyclopedia)seaweed, name commonly used for the multicellular marine algae. Simpler forms, consisting of one cell (e.g., the diatom) or of a few cells, are not generally called seaweeds; these tiny plants help to...

shark

(Encyclopedia)shark, member of a group of almost exclusively marine and predaceous fishes. There are about 250 species of sharks, ranging from the 2-ft (60-cm) pygmy shark to 50-ft (15-m) giants. They are found in ...

antibiotic

(Encyclopedia)antibiotic, any of a variety of substances, usually obtained from microorganisms, that inhibit the growth of or destroy certain other microorganisms. Although for centuries preparations derived from ...

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 ...