Exon
Exon explained in an easy to understand way:
Imagine you're assembling a jigsaw puzzle and only some pieces form the actual image you want to display, while others are just filler pieces not used in the final picture. Just like in the puzzle, where you need to identify and use only the pieces that contribute to the complete image, in genetics, exons are the specific sequences of DNA that are selected to form the final mRNA, much like choosing only the needed puzzle pieces for the image. In this way, exons are akin to the essential puzzle pieces that, when pieced together, create the complete and functional picture, or in biological terms, the mRNA that will be translated into proteins.
Practice Version
Exon: A DNA sequence that codes part of the final mRNA. Exon. An exon is a segment of a DNA or RNA molecule that contains information coding for a protein or peptide sequence.