Final answer:
The observable physical features of an organism are referred to as its phenotype, which includes traits like color and shape. The phenotype is shaped by genetic and environmental factors and is key in fields like genetics and taxonomy.
Step-by-step explanation:
The observable physical features of an organism comprise its phenotype. Phenotype includes traits such as color, shape, and size, which result from both genetic inheritance and environmental influences. Understanding an organism's phenotype is central to the fields of genetics and evolutionary biology, as it is the physical manifestation of the organism's genotype (the genetic code).
Morphology, another important term, refers to the form and structure of an organism and is often used for classification based on physical traits. For example, Linnaean classification system, which classifies organisms into a hierarchical taxonomy, is fundamentally based on the observable physical traits that are part of an organism's phenotype. Through the study of phenotype, scientists can determine a great deal of information about an organism's anatomy and physiology, and how these aspects relate to the organism's environment and survival strategies.