Use the circular codon table to complete the DNA triplets, mRNA codons, tRNA anticodons, and amino acids in the table below. 1. What 3 codons act as termination signals? 2. What codon means start? 3. List ALL of the codons for leucine. 4. Phenylalanine –. 5. Serine –. 6. Isoleucine –. 7. Valine –. 9. Glycine –. 10. Alanine –. 11.