Quiz: Remember the definition of mal de mer?
1911, from German Gen, coined 1905 by Danish scientist Wilhelm Ludvig Johannsen (1857-1927), from Greek genea "generation, race" (see genus). De Vries had earlier called them pangenes. Gene pool is attested from 1950.
A hereditary unit that occupies a specific location on a chromosome, determines a particular characteristic in an organism by directing the formation of a specific protein, and is capable of replicating itself at each cell division.
A segment of DNA, occupying a specific place on a chromosome, that is the basic unit of heredity. Genes act by directing the production of RNA, which determines the synthesis of proteins that make up living matter and are the catalysts of all cellular processes. The proteins that are determined by genetic DNA result in specific physical traits, such as the shape of a plant leaf, the coloration of an animal's coat, or the texture of a person's hair. Different forms of genes, called alleles, determine how these traits are expressed in a given individual. Humans are thought to have about 35,000 genes, while bacteria have between 500 and 6,000. See also dominant, recessive. See Note at Mendel.