what is the name of the enzyme that adds new nucleotides to build mrna

The enzyme that adds new nucleotides to build mRNA is RNA polymerase.

Quick Scoop: Short + Sweet

• During transcription , a DNA sequence is copied into mRNA.

• The enzyme that actually builds the mRNA strand by adding RNA nucleotides is RNA polymerase.

• It reads the DNA template and strings together complementary RNA bases (A, U, C, G) to form the mRNA molecule.

In other words: if transcription is like copying a recipe from a cookbook, RNA polymerase is the “scribe” doing the writing.

TL;DR: The enzyme that adds new nucleotides to build mRNA is RNA polymerase.

Information gathered from public forums or data available on the internet and portrayed here.