Define the term "gene expression."

The term "gene expression" specifically refers to the process by which the information encoded in a gene is utilized to produce a functional product, typically a protein or RNA molecule. This process involves two key stages: transcription, where the DNA sequence of the gene is transcribed into messenger RNA (mRNA), and translation, where the mRNA is used as a template to synthesize a protein. This is a fundamental biological process, as it determines the cellular functions and traits of an organism by producing the necessary proteins that carry out various roles within the cells.

In contrast, the variation of traits visible in an organism pertains to phenotypic expression, which results from the combined influence of gene expression and environmental factors. Mapping genes on a chromosome involves genetic analysis techniques that identify the locations of genes, which is different from the actual expression of those genes. The process of gene mutation refers to changes in the DNA sequence of a gene, which can affect gene function or expression but does not define gene expression itself. Thus, the first choice accurately encapsulates the concept of gene expression by highlighting its role in the synthesis of functional products derived from genetic information.