Campbell Biology Chapter 16-17

Last update by hturek on 10/21/2014
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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.

Answer:

A) many noncoding stretches of nucleotides are present in mRNA.

This is not accurate... noncoding stretches of nucleotides are present in preRNA but are almost entirely cut out in RNA modification. The correct answer is C) many nucleotides are required to code for each amino acid.

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