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sediment

(Encyclopedia)sediment, mineral or organic particles that are deposited by the action of wind, water, or glacial ice. These sediments can eventually form sedimentary rocks (see rock). Sediments form sedimentary ...

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...

colloid

(Encyclopedia)colloid kŏlˈoid [key] [Gr.,=gluelike], a mixture in which one substance is divided into minute particles (called colloidal particles) and dispersed throughout a second substance. The mixture is also...

electron

(Encyclopedia)electron, elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the ...

muscle

(Encyclopedia)muscle, the contractile tissue that effects the movement of and within the body. Muscle tissue in the higher animals is classified as striated, smooth, or cardiac, according to its structure and funct...

botany

(Encyclopedia)botany, science devoted to the study of plants. Botany, microbiology, and zoology together compose the science of biology. Humanity's earliest concern with plants was with their practical uses, i.e., ...

skin cancer

(Encyclopedia)skin cancer, malignant tumor of the skin. The most common types of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma. Rarer forms include mycosis fungoides (a type of lymphom...

ant

(Encyclopedia)ant, any of the 2,500 insect species constituting the family Formicidae of the order Hymenoptera, to which the bee and the wasp also belong. Like most members of the order, ants have a “wasp waist,�...

submersible

(Encyclopedia)submersible, small, mobile undersea research vessel capable of functioning in the ocean depths. Development of a great variety of submersibles during the later 1950s and 1960s came about as a result o...

coal

(Encyclopedia)coal, fuel substance of plant origin, largely or almost entirely composed of carbon with varying amounts of mineral matter. Coal is found in beds or seams interstratified with shales, clays, sands...