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life
(Encyclopedia)life, although there is no universal agreement as to a definition of life, its biological manifestations are generally considered to be organization, metabolism, growth, irritability, adaptation, and ...meristem
(Encyclopedia)meristem mĕrˈistĕmˌ [key], a specialized section of plant tissue characterized by cell division and growth. Much of the mature plant's growth is provided by meristems. Apical meristems found at th...endoderm
(Encyclopedia)endoderm ĕnˈdədûrmˌ [key], in biology, inner layer of tissue formed in the gastrula stage of the developing embryo. At the end of the blastula stage, cells of the embryo are arranged in the form ...sperm
(Encyclopedia)sperm or spermatozoon spûrˌmətəzōˈən, –zōˈŏn [key], in biology, the male gamete (sex cell), corresponding to the female ovum in organisms that reproduce sexually. In higher animals the spe...mesoderm
(Encyclopedia)mesoderm, in biology, middle layer of tissue formed in the gastrula stage of the developing embryo. At the end of the blastula stage, cells of the embryo are arranged in the form of a hollow ball. Con...aging
(Encyclopedia)aging, in biology, cumulative changes in an organism, organ, tissue, or cell leading to a decrease in functional capacity. In humans, aging is associated with degenerative changes in the skin, bones, ...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., ...tissue
(Encyclopedia)tissue, in biology, aggregation of cells that are similar in form and function and the intercellular substances produced by them. The fundamental tissues in animals are epithelial, nerve, connective, ...inheritance, in biology
(Encyclopedia)inheritance, in biology: see heredity. ...resistance, in biology
(Encyclopedia)resistance, in biology: see immunity. ...Browse by Subject
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