In biology, any difference between cells, individual organisms, or groups of organisms within a species caused either by genetic differences (variation in genotype) or by the effect of environmental factors on the expression of genetic potentials (variation in phenotype). Variation may be shown in physical appearance, metabolism, fertility, mode of reproduction, behaviour, learning and mental ability, and other obvious or measurable characters. Genotypic variations are caused by differences in number or structure of chromosomes or by differences in the genes carried by the chromosomes. Eye colour, body form, and disease resistance are genotypic variations. Phenotypic variations may result from factors such as climate, food supply, and actions of other organisms. Phenotypic variations also include stages in an organism's life cycle and seasonal variations in an individual. Because they do not involve hereditary alteration and in general are not transmitted to future generations, phenotypic variations are not important in evolution. Seealso polymorphism.
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Genetic makeup of an organism. The genotype determines the hereditary potentials and limitations of an individual. Among organisms that reproduce sexually, an individual's genotype comprises the entire complex of genes inherited from both parents. Sexual reproduction guarantees that each individual has a unique genotype, except for identical twins, who come from the same fertilized egg. Seealso phenotype, variation.
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BEETHOVEN: Variations on a Waltz of Diabelli, op. 120. Piano Sonata No. 29 in B[musical flat], op. 106, "Hammerklavier"/ SCHUBERT: Variation on a Waltz of Diabelli, D 718/ BEETHOVEN: Variations on a Waltz of Diabelli, op. 120
Nov 01, 2010; BEETHOVEN variations on a Waltz of Diabelli, op. 120. Piano Sonata No. 29 in B[musical flat], op. 106, "Hammerklavier."...
BRAHMS: Variations on an Original Theme, op. 21/ 1. Variations on a Hungarian Song, op. 21/ 2. Variations and Fugue on a Theme by Handel, op. 24. Paganini Variations, Books I and II
May 01, 2010; BRAHMS variations on an Original Theme, op. 21/1. variations on a Hungarian Song, op. 21/2. variations and...