Question

RNA synthesis is always 5' to 3' because: A. the unwinding of the double-stranded DNA can only move one direction B. the structure of ATP restricts 3' to 5' polymerization into RNA C. RNA synthesis can move in the 3' to 5' direction D. None of these E. nucleotides can only be added to an available 3'-OH group on the transcript terminus F. nitrogenous bases cannot pair up in the 3' to 5' direction

Answer 1

The correct answer is: E) nucleotides can only be added to an available 3'-OH group on the transcript terminus.

Step-by-step explanation:

RNA synthesis is a key process that happens in the nucleus and is important for the synthesis of proteins. In order to Transcription (the process in which a strand of RNA is synthesized from a specific gene) to occur, the enzyme RNA Polymerase is needed to catalyze it. However, this process has a particular way to operate, since the synthesis of the new RNA strand can only be from 5' to 3' because the nucleotides can only be added to an available 3'-OH group on the transcript terminus.

Answer 2

The correct answer is option E. "nucleotides can only be added to an available 3'-OH group on the transcript terminus".

Step-by-step explanation:

RNA synthesis is catalyzed by an enzyme called RNA polymerase. RNA polymerase always catalyze the synthesis of new RNA from 5' to 3' because nucleotides can only be added to an available 3'-OH group on the transcript terminus. This has been confirmed in labeling experiments with γ-32P substrates which establish the presence of a triphosphate moiety in transcripts with either pppG or pppA.