The image shows the process of splicing. This is a stage of RNA processing where introns are removed from the mRNA strand and exons are left. <u><em>Introns </em></u>do not code for proteins so it is taken out. <em><u>Exons </u></em>on the other hand, do so it is left on. Notice in the end, all you have is a pink strip of mRNA, which are the exons. All the purple blocks are removed. The ones that remove the introns are called <em><u>spliceosomes</u></em><em>, </em>which are the little BLUE things that are carrying out the purple blocks.
Explanation: The process that is shown here is called as Splicing. This is a biological term which is used to define the process in which there is a removal of the non functional part of the DNA.
In most of the eukaryotic cell the the coding regions (exon) are hindered by the non coding regions (intron). During the process of transcription the whole segment containing the intron and exon are copied.
The pre-mRNA undergoes a process called as splicing in which the non coding regions are removed and then the mRNA is only left with the functional part that is exons.