Which of the following is a stop codon?

The cell-free system was helpful in which of the following?

Codons of glycine are

In $mRNA$,$AUG$ is the initiation codon and $UAA$,$UAG$,and $UGA$ are termination codons; therefore,a polypeptide cannot be synthesized beyond any of these triplets to the end of the $mRNA$. Which one of the following $mRNA$ sequences can be translated completely?

The diamond code proposal was made by:

Which of the following is not a property of the genetic code?