Question

Is cDNA the same as mRNA ?

Answer 1

Hint: Reverse transcription is used in the laboratory to synthesise this strand of DNA from mRNA. Because cDNA is formed following intron splicing and, as a result, a mature mRNA, it differs from genomic DNA. There are only a few genes in cDNA that code for proteins.

Complete answer:
Francis Crick suggested the key concept that gene information goes from DNA to RNA to protein. However, gene information moves from RNA to DNA in some virus-like retroviruses. The process of converting RNA to DNA is known as reverse transcription.
Using this technology, scientists were able to generate complementary DNA (cDNA) from mRNA strands. To make cDNA from mRNA, the enzyme reverse transcriptase is used.
Reverse transcription from an mRNA template produces cDNA, or complementary DNA. It's an mRNA DNA copy.
A specific mRNA can be used to make a cDNA probe. A template is mRNA, which encodes a certain protein. A cDNA can be employed as a probe to hybridise with a specific gene sequence thanks to the actions of reverse transcriptase and DNA polymerase.
Because cDNA does not contain the intron, it has a wide range of applications. Gene probes, gene cloning, and the creation of a cDNA library are all done with cDNA. In prokaryotes, it's employed to clone the eukaryotic gene.

Note:
cDNA synthesis-
The poly-adenylated tail is linked to the $$3^{\prime }$$ end of the mRNA. The primer is added as a complement to the poly-adenylate tail, along with the reverse transcriptase enzyme. The strands that result are mRNA-DNA hybrid strands. After that, an alkaline solution degrades the mRNA. The free $$3^{\prime }$$ end of the cDNA creates a hairpin loop-like structure, and the second strand is generated utilising primer and DNA polymerase III. Finally, the hairpin loop is cleaved by the S$$1$$ nuclease enzyme. Finally, the original copy of mRNA is used to make double-stranded cDNA.