A transcription unit that is 8,000 nucleotides long may use 1,200 nucleotides to make a protein consisting of approximately 400 amino acids. This is best explained by the fact that
A) many noncoding stretches of nucleotides are present in mRNA.
B) there is redundancy and ambiguity in the genetic code.
C) many nucleotides are needed to code for each amino acid.
D) nucleotides break off and are lost during the transcription process.
E) there are termination exons near the beginning of mRNA.

Question

Quizplus · Accepted Answer

The presence of noncoding stretches of nucleotides in mRNA leads to a larger transcription unit than the actual length of the protein-coding sequence. This can result in a 8,000 nucleotide transcription unit being used to make a protein consisting of only 1,200 nucleotides, allowing for regulation of gene expression and potentially creating alternative mRNA splicing patterns.

A Transcription Unit That Is 8,000 Nucleotides Long May Use