Introns are non-coding segments of DNA found within genes. Unlike exons, which are the coding regions that provide instructions for making proteins, introns do not contribute to the final protein product. During the process of gene expression, introns are removed from the pre-mRNA transcript through a process called splicing, allowing the exons to be joined together. Although introns do not code for proteins, they may play important roles in regulating gene expression and contributing to the diversity of proteins through alternative splicing. This means that a single gene can produce multiple protein variants, enhancing the complexity of biological functions.