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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...

Mollusca

(Encyclopedia)Mollusca məlŭsˈkə [key], taxonomic name for the one of the largest phyla of invertebrate animals (Arthropoda is the largest) comprising more than 50,000 living mollusk species and about 35,000 fos...

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...

pollution

(Encyclopedia)pollution, contamination of the environment as a result of human activities. The term pollution refers primarily to the fouling of air, water, and land by wastes (see air pollution; water pollution; s...

fish, in zoology

(Encyclopedia)CE5 Anatomy of a ray-finned fish fish, limbless aquatic vertebrate animal with fins and internal gills. Traditionally the living fish have been divided into three class: the primitive jawless fish...

virus

(Encyclopedia)CE5 Structure of a tobacco mosaic virus, an RNA-containing virus virus, parasite with a noncellular structure composed mainly of nucleic acid within a protein coat. Most viruses are too small (100...

chemistry

(Encyclopedia)chemistry, branch of science concerned with the properties, composition, and structure of substances and the changes they undergo when they combine or react under specified conditions. Organic chemi...

Echinodermata

(Encyclopedia)CE5 Internal anatomy of a sea star, representative of the phylum Echinodermata Echinodermata əkīˌnōdûrˈmətə [key] [Gr.,=spiny skin], phylum of exclusively marine bottom-dwelling invertebra...

space exploration

(Encyclopedia)CE5 Moon mission assembly CE5 Stages in a moon mission shown counterclockwise from launching on the first day to splashdown on the ninth day. space exploration, the investigation of physical co...

science

(Encyclopedia)science [Lat. scientia=knowledge]. For many the term science refers to the organized body of knowledge concerning the physical world, both animate and inanimate, but a proper definition would also hav...

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