RNA Synthesis is Always 5' to 3' Because

Question

RNA synthesis is always 5' to 3' because:
A)the unwinding of the double-stranded DNA can only move one direction.
B)nucleotides can only be added to an available 3'-OH group on the transcript terminus.
C)nitrogenous bases cannot pair up in the 3' to 5' direction.
D)the structure of ATP restricts 3' to 5' polymerization into RNA.
E)RNA synthesis can move in the 3' to 5' direction.

Accepted Answer

RNA synthesis requires the addition of nucleotides to the 3'-OH group on the existing RNA strand. Therefore, RNA synthesis can only proceed in the 5' to 3' direction.