What is the Difference Between Introns and Exons?

The main difference between introns and exons lies in their function in the genome and their presence in the mature RNA molecule. Here are the key differences:

• Function: Introns are non-coding sequences found in DNA or RNA, while exons are the coding portions of DNA or RNA. Introns are removed via RNA splicing, and exons are joined together to form coding sequences that produce proteins.
• Presence in RNA: Introns are found in the primary RNA transcript (hnRNA), which is an unprocessed version of the RNA molecule. Exons, on the other hand, are present in the mature mRNA after post-transcriptional modification.
• Conservation: The sequence of introns frequently changes over time, making them less conserved. In contrast, exons are highly conserved sequences, meaning they do not frequently change with time.
• Location: Introns are found in both prokaryotes and eukaryotes, while exons are present in eukaryotes only.

In summary, introns are non-coding sequences that are removed during RNA splicing, and exons are coding sequences that remain in the mature mRNA to code for proteins. Introns are less conserved than exons, which are highly conserved and function to produce proteins.

Comparative Table: Introns vs Exons

Here is a table comparing the differences between introns and exons:

In summary, introns are non-coding DNA sequences that are removed during RNA splicing, while exons are coding DNA sequences that are joined together to form mature mRNA. Introns are present only in eukaryotes, whereas exons are found in both prokaryotes and eukaryotes.