Class 12th Biology 2016 Set1 Outside Delhi Board Paper Solution
Question 25
Explain the processing the hnRNA needs to undergo before becoming functional mRNA eukaryotes.
Answer
The precursor of mRNA, i.e., hnRNA, contains both introns and exons. Introns are removed and exons are joined by a process called splicing. The remaining mRNA is processed in two ways :
Capping : An unusual nucleotide (methyl gunosine triphosphate) is added to the 5′-end of hnRNA.
Tailing : Adenylate residues (200-300) are added at 3′-end in a template independent manner. When hnRNA is full processed, it is known as mRNA, which is transported out of the nucleous.
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