What are exons?

Exons are the segments of DNA that are transcribed into mRNA and ultimately translated into proteins. They represent the coding portions of a gene and are responsible for specifying the amino acid sequence of a protein. During the process of gene expression, the entire gene is initially transcribed, including both exons and introns (the non-coding segments). However, during RNA processing, introns are removed, and exons are spliced together to form the mature mRNA molecule that enters the translation process. This is why exons are crucial for the formation of functional proteins, as they directly contribute to the coding sequence that determines the structure and function of proteins in living organisms.