Match List- I with List - II.

List - I		List - II
(A)	Initiation factor	(i)	Tailing
(B)	Introns	(ii)	Rho(ρ)
(C)	Termination factor	(iii)	Sigma(σ)
(D)	Adenylate residue	(iv)	Splicing

Concept:

• Transcription is the process of copying the genetic information from one strand of DNA onto the RNA.
• Transcription involves 3 basic steps:
  • Initiation
  • Elongation
  • Termination
• In eukaryotes, the mRNA is formed is the form of heterogenous RNA (hnRNA).
• This hnRNA needs to go through some post-transcriptional modification processes to form the mature mRNA that can be translated into polypeptide.

Important Points

• Initiation Factor - 
  • In prokaryotic transcription, RNA polymerase enzyme binds at the promoter site of DNA with the help of sigma (σ) factor and initiates transcription.
  • The sigma factor is also known as the initiation factor.
• Introns - 
  • In eukaryotes, the primary transcribed RNA has both exons and introns and is known as the hn-RNA or heterogeneous nuclear RNA. 
  • Introns are the non-coding sequence of RNA that are removed before RNA is translated.
  • The exons are the part of RNA that translates to a protein.
  • Splicing is the process of removing introns and the joining together of exons in the primary RNA transcript.
  • This forms the mature RNA from the hn-RNA.
• Termination Factor - 
  • Transcription termination is carried out by the Rho factor (ρ) that binds to the terminator site.
  • When the Rho factor comes across the RNA polymerase enzyme, the RNA is unwound from the DNA.
  • The nascent RNA is released along with the enzyme.
  • The DNA double helix reforms and Rho protein dissociates, terminating the transcription process.
• Adenylate residue - 
  • Polyadenylation is the process of adding about 200-300 adenylate residues to the 3'-end of the newly formed RNA.
  • These residues form a poly-A tail at the 3'-end of the mRNA and thus, this process is also known as tailing.
  • In an eukaryotic cell, the RNA molecules have the risk of being degraded by cytoplasmic enzymes when the RNA is transported from nucleus to cytoplasm.
  • Polyadenylation helps in protecting the 3'-end of the coding sequence of the RNA from digestive enzymes.

Corrected Table:

Hence, the correct answer is option 4.