PHENOTYPE
The phenotype of an organism is the assemblage of the interior features, which can be observed. They are: morphology, physiology and behavour. During the lifetime of an organism its phenotype can change, unlike its genotype, which defines the phenotype and remains constant during the whole life of an organism. However, the correspondence between the genotype and the penotype is not completely direct. There is no a pair of individuals with identical phenotypes, though these individuals can be similar in respect of one or several features concerned. Moreover, the individuals, which possess similar phenotypes in respect of a certain feature, are not necessarily identic genotypically.