PHENOTYPE AND GENOTYPE Definitions: phenotype is the constellation of observable traits; genotype is the genetic endowment of the individual. Phenotype = genotype + development (in a given environment). To consider these in the context of evolutionary biology, we want to know how these two are related. In a narrow "genetic" sense, the genotype defines the phenotype. But how, in and evolutionary sense, does the phenotype "determine" the genotype? Selection acts on phenotypes because differential reproduction and survivorship depend on phenotype. If the phenotype affecting reproduction or survivorship is genetically based, then selection can winnow out genotypes indirectly by winnowing out phenotypes. How do we get from genotype to phenotype? Central dogma : DNA via transcription to RNA via translation to protein ; proteins can act to alter the patterns and timing of gene expression which can lead to cytodifferentiation where cells take on different states; cell communication can lead to
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This note was uploaded on 11/05/2011 for the course BIOLOGY MCB2010 taught by Professor Jessicadigirolamo during the Fall '10 term at Broward College.