Which enzyme synthesizes the RNA primer required for DNA replication?
Primase is a specialized RNA polymerase that synthesizes short RNA primers to provide a free 3-prime hydroxyl group for DNA polymerase to start synthesis.
Question 172 of 668
📘 CLASS XII
DNA Polymerase adds nucleotides to which end of the growing strand?
DNA Polymerase can only add new nucleotides to the free 3-prime hydroxyl group of the growing DNA chain.
Question 173 of 668
📘 CLASS XII
The lagging strand is synthesized as short segments called?
Because DNA polymerase synthesizes only in the 5-to-3 direction, the lagging strand (which runs 3-to-5) must be synthesized discontinuously in short pieces called Okazaki fragments.
Question 174 of 668
📘 CLASS XII
Which enzyme joins Okazaki fragments together?
DNA Ligase acts as a molecular glue, sealing the nicks between Okazaki fragments by forming phosphodiester bonds to create a continuous strand.
Question 175 of 668
📘 CLASS XII
The enzyme responsible for relieving tension (supercoiling) ahead of the replication fork is?
Topoisomerase (specifically DNA Gyrase in prokaryotes) relieves the torsional strain or supercoiling generated ahead of the replication fork as the DNA unwinds.
Question 176 of 668
📘 CLASS XII
DNA replication is described as?
Replication is semi-conservative (one old, one new strand) and semi-discontinuous (leading strand is continuous, lagging strand is discontinuous).
Question 177 of 668
📘 CLASS XII
The segment of DNA that participates in transcription is called?
A Transcription Unit is the segment of DNA defined by a promoter, the structural gene, and a terminator that is transcribed into RNA.
Question 178 of 668
📘 CLASS XII
The Promoter is located towards which end of the coding strand?
By convention, the position of the promoter is defined by the coding strand, and it is located at the 5-prime end (upstream) of the structural gene.
Question 179 of 668
📘 CLASS XII
Which factor is required for the initiation of transcription in prokaryotes?
The Sigma factor binds to the RNA Polymerase core enzyme to enable it to recognize the promoter sequence and initiate transcription.
Question 180 of 668
📘 CLASS XII
Which factor is required for the termination of transcription in prokaryotes?
The Rho factor binds to the RNA polymerase or the nascent RNA to facilitate the termination of transcription and release of the transcript.
