The relationship between genotype and phenotype is fundamental in genetics. The genotype refers to the genetic makeup of an organism, while the phenotype is the observable expression of that genotype, influenced by environmental factors. Essentially, the genotype provides the blueprint, but the phenotype represents how that blueprint manifests in traits like appearance or behavior. Understanding this relationship is crucial for studies in evolution, breeding, and disease research, as it allows scientists to predict how genetic variations can lead to different physical attributes and capabilities.