The term for the relationship between genes and physical traits is phenotypic expression. This encompasses how genetic information, inherited from parents, translates into observable traits, such as appearance, behavior, and physiological characteristics. Various factors, including environmental influences and gene-environment interactions, can impact this expression, leading to variations within populations. Understanding phenotypic expression is essential for fields such as genetics, evolutionary biology, and medical research, aiding in predicting heritable traits and associated health conditions.