How is the trait exhibited in an organism, like brown hair or blue eyes, referred to?

The term used to describe the observable characteristics or traits of an organism, such as brown hair or blue eyes, is known as the phenotype. Phenotype encompasses all the physical expressions of genetic information, which includes an organism's morphology, development, biochemical properties, and behavior, as influenced by both its genetic inheritance (genotype) and environmental factors. This concept allows scientists to study and classify organisms based on their visible traits, which can be crucial in fields like genetics, biology, and ecology.

Understanding phenotype is essential for various biological applications, including selective breeding, conservation efforts, and the study of evolutionary processes. This contrasts with genotype, which refers specifically to the genetic makeup of an organism, encompassing alleles that may not always manifest in visible traits.