In biology, particularly genetics and evolutionary biology, the phenotype refers to the observable characteristics or traits of an organism, resulting from the interaction of its genetic makeup (genotype) with environmental factors. These observable traits can include physical features, biochemical properties, physiological functions, and behaviors.
The phenotype represents the expression of genes in an organism, influenced by both its inherited genetic information and the environmental conditions in which it develops and lives. While the genotype provides the genetic instructions for building and regulating the organism, the phenotype is what can be directly observed and measured.
Examples of phenotypic traits in humans include eye color, height, blood type, susceptibility to certain diseases, and behavioral tendencies. In plants, phenotypic traits could include flower color, leaf shape, growth rate, and resistance to pests.
Understanding phenotypes is essential for studying various biological processes, including evolution, development, and disease. By analyzing phenotypic variation within populations, scientists can infer underlying genetic differences, environmental influences, and the complex interactions between genes and the environment.