[Campbell Biology P.390] Which of the following statements accurately describes the genetic ... | Practice Question

Which of the following statements accurately describes the genetic code as presented in the text?

  • A: All 64 codons specify unique amino acids, ensuring no ambiguity.
  • B: The codon AUG serves solely as a start signal for protein synthesis.
  • C: The genetic code exhibits redundancy, meaning multiple codons can specify the same amino acid, but it is unambiguous, meaning one codon specifies only one amino acid.
  • D: The genetic code is universal, applying only to simpler organisms like bacteria.

Explanation

The text explicitly states: 'Notice in Figure 17.6 that there is redundancy in the genetic code, but no ambiguity. For example, although codons GAA and GAG both specify glutamic acid redundancy , neither of them ever specifies any other amino acid no ambiguity .' It also mentions that the genetic code is 'nearly universal, shared by organisms from the simplest bacteria to the most complex plants and animals,' and that AUG also functions as a start signal, not solely as a start signal.