Question

A scientist puts mRNA nucleotide chains that contain only Uracil (U) in a test tube. That test tube allows protein synthesis to be initiated. After a short time, the scientist finds that the test tube is full of chains of the amino acid phenylalanine. Only phenylalanine is present and no other amino acid is observed. What does this experiment demonstrate?

Answer 1

An amino acid can be formed by combining 3 nucleobases. In the test, the only nucleobase the mRNA is uracil. That means the possible combination of the nucleobase should be only UUU. Since there is only 1 possible combination, there should be 1 possible amino acid that can be formed.
Phenylalanine should have UUU codon.