How are the accuracy of DNA and mRNA codes assured?

Question

anonymous · Answer

Earlier, I talked a little bit about "transcription." 

TRANSCRIPTION is when we take DNA, 
and we create RNA from it. 

Well, TRANSCRIPTION is done using a special enzyme, called RNA POLYMERASE. 

The RNA Polymerase is in charge of making sure that all DNA bases get their correct partners. 

We can call this "proof-reading activity," 
because the RNA Polymerase proofreads all of the DNA RNA base pair partners. 

Again, 

A needs to go with U
T needs to go with A
G needs to go with C
C needs to go with G

Whenever the RNA Polymerase sees a pair that is incorrect, 
it will remove it, and repair it. 

That's what it's supposed to do, anyhow.
But I bet you that sometimes, mistakes are made.