What is the role of a gene?

A gene is a segment of DNA that serves as the blueprint for the synthesis of proteins, which play crucial roles in the functioning of an organism. The primary role of a gene is to code for specific proteins, which ultimately influence various traits exhibited by an organism. This is achieved through the process of transcription and translation, where the information contained in the DNA is converted into messenger RNA and then used to assemble amino acids into proteins.

These proteins can affect physical characteristics (such as eye color, height, etc.) or play roles in physiological processes (such as enzymes and hormones). Therefore, the correct answer emphasizes the dual role of a gene: not only does it code for proteins, but it also determines traits based on the function of those proteins.

Understanding this function of genes is foundational in genetics, illustrating how variability in gene sequences can lead to diversity in traits among individuals within a species.