What is a gene?

A gene is defined as a segment of DNA that contains the necessary information to produce a specific protein, which may affect an organism's traits and functions. This definition underscores the role of DNA as the hereditary material in living organisms, serving as the blueprint for all genetic information. Each gene consists of sequences of nucleotides, which dictate the structure and function of proteins by specifying the order of amino acids.

The other options do not accurately describe a gene. While RNA plays a crucial role in the process of gene expression and can have functions beyond coding for proteins, it is not classified as a gene itself. Carbohydrates are organic molecules that serve energy storage and structural roles, distinctly different from the genetic function of genes. Additionally, organelles are specialized structures within cells that carry out specific tasks, such as energy production or protein synthesis, but they are not genes. Understanding the role of genes is fundamental to genetics and molecular biology, as they are the driving force behind the traits and functions of all living organisms.