Question

NASA scientists found on Mars a molecule similar to DNA, except it only uses three bases (A, C, T). Just like DNA, however, it is transcribed into an mRNA-like transcript. Assuming the following: (1) that proteins are made from this mRNA transcript, (2) that 30 amino acids exist for this organism, and (3) that the code is known to be degenerate, what is the minimum number of bases likely to be in a single codon?

Answer 1

Answer: 4 codon

Explanation:

We have two important data, that a molecule brought from Mars uses only three bases (A, C and T) and that it has 30 amino acids

Knowing that to encode 30 amino acids with 3 bases, you need to have 4 bases in your codon.

We have the possibility that having 4 bases can be encoded enough like this:

3 ^ 4 = 81.

however if we do the same procedure with 3 basic codons we will get an insufficient result

  3 ^ 3 = 27

so the most likely codon number is 4