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Delbrück, Max Ludwig Henning

(Encyclopedia)Delbrück, Max Ludwig Henning dĕlˈbrük [key], 1906–1981, American biophysicist, b. Berlin, Germany. Ph.D, Univ. of Göttingen, 1930. He spent most of his career as a professor at the California I...

fertilization

(Encyclopedia)CE5 Fertilization of an egg cell fertilization, in biology, process in the reproduction of both plants and animals, involving the union of two unlike sex cells (gametes), the sperm and the ovum, f...

Robbins, Frederick Chapman

(Encyclopedia)Robbins, Frederick Chapman, 1916–2003, American physician, b. Auburn, Ala., grad. Univ. of Missouri, 1938, M.D. Harvard, 1940. He served on the staff of Children's Hospital, Boston, and at Harvard, ...

Thomas, Lewis

(Encyclopedia)Thomas, Lewis, 1913–93, American physician and biologist, b. Flushing, New York. In his youth he often accompanied his physician father on his rounds and decided early on to be a doctor or a writer....

ovum

(Encyclopedia)ovum ōˈvəm [key], in biology, specialized plant or animal sex cell, also called the egg, or egg cell. It is the female sex cell, or female gamete; the male gamete is the sperm. The study of the ovu...

Yonath, Ada E.

(Encyclopedia)Yonath, Ada E., 1939–, Israeli crystallographer, Ph.D. Weizmann Institute of Science, Rehovat, Israel, 1968. Yonath has been a researcher and professor at the Weizmann Institute since 1970. She was ...

secretion

(Encyclopedia)secretion, in biology, substance elaborated by the living material of an animal or plant. Secretions in humans can be produced by a single cell or by a group of cells commonly called a gland. Some sec...

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 ...