Question

Match column-I with column-II and select the correct combination from the given options.

	Column I		Column II
A	Sigma factor	I	5’-3’
B	Capping	II	Initiation
C	Tailing	III	Termination
D	Coding Strand	IV	5’ end
		V	3’ end

(A) A-III; B-V; C-IV; D-II
(B) A-II; B-IV; C-V; D-I
(C) A-II; B-IV; C-V; D-III
(D) A-III; B-V; C-IV; D-I

Answer 1

Hint: Transcription is a process in which single stranded RNA is synthesised from double stranded DNA. The hn-RNA formed undergoes post transcriptional process in order to form mature mRNA, these post transcriptional processes include splicing, tailing and capping. Sigma factor is initiation factor and rho factor is termination factor.

Complete Step by Step Answer:
A DNA fragment is copied into RNA during transcription. Messenger RNA is the term for DNA segments that are translated into RNA molecules that can encode proteins. Non-coding RNAs are RNA molecules that contain copies of other DNA sequences. An RNA primary transcript is chemically altered after transcription from a gene to produce a mature, functional RNA molecule that can then leave the nucleus and carry out biological functions. This process is known as post-transcriptional modification or co-transcriptional modification and is common to most eukaryotic cells.
A protein called sigma factor is required for the beginning of transcription in bacteria. It is a bacterial transcription initiation factor that permits RNA polymerase (RNAP) to specifically bind to gene promoters. In eukaryotes, capping is a form of post-transcriptional modification in which a changed base is tacked onto the mRNA's 5' end. This helps with ribosome binding during translation and safeguards the developing mRNA from destruction. The 3' end of the mRNA undergoes yet further post-transcriptional alteration, known as the poly "A" tail, in which a tail made up of many "A" residues is added. The DNA strand that runs from 5' to 3' and whose base sequence matches the base sequence of the RNA transcript generated is known as the coding strand in transcription.
So, option (B) is correct.

Note: Various factors are required for the process of transcription to start, process and finally terminate. Sigma factor is required for initiation, RNA polymerase for elongation and rho factor for termination of transcription. RNA undergoes capping and tailing in order to be protected from degrading.