Dna polymerase has multiple mechanisms for editing and error correction, whereas the capacity for error correction in rna polymerases seems to be quite limited. however, like a dna mutation, an rna polymerase error in transcription can cause production of a mutated protein. the limited error correction of rna polymerase seems to be inconsistent with the potentially serious consequence of producing a protein with an altered amino acid sequence. a) defective proteins are often degraded quickly, making their effects temporary. b) single amino acid substitutions caused by errors in mrna transcription would not affect protein function. c) unlike dna mutations, mrna transcripts have short half-lives and are not inherited across many generations. d) degradation of defective proteins activates mrna repair pathways e) rna polymerases synthesize many transcripts per gene, so only a small fraction of rna transcripts would have errors. f) ch mrna molecule is only translated once and then degraded.

D) Degradation of defective proteins activates mRNA repair pathways

Explanation:

A recent publication (J Phys Condens Matter. 2013. 18;25(37):374104.) provided the information on this matter. According to researcher RNA polymerase have ability to backtrack and translocate the error on both RNA transcript and DNA template. By doing so RNA polymerase cleave the defective part on RNA transcriptome by the process called proofreading. While proofreading contribute in accuracy of transcription but on contrary it also slower the process of transcription.

for the points

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.