Who discovered the chemical method for the synthesis of $RNA$ molecules with defined combinations of bases?

If in a test tube,$mRNA$ of $E. coli$ cells and $tRNAs$ from the body of rats are taken and a sufficient number of amino acids are added,then the polypeptide synthesized will be of the nature of

Who proposed the 'one gene one enzyme' hypothesis?

Hargobind Khorana received the Nobel Prize for his work on:

What role does messenger $RNA$ play in the synthesis of proteins?

The 'one gene, one enzyme' hypothesis was proposed by . . . . . . .