<P> The Nirenberg and Matthaei experiment was a scientific experiment performed on May 15, 1961, by Marshall W. Nirenberg and his post doctoral fellow, J. Heinrich Matthaei . The experiment deciphered the first of the 64 triplet codons in the genetic code by using nucleic acid homopolymers to translate specific amino acids . </P> <P> In the experiment, an extract from bacterial cells that could make protein even when no intact living cells were present was prepared . Adding an artificial form of RNA, poly - U, to this extract caused it to make a protein composed entirely of the amino acid phenylalanine . This experiment cracked the first codon of the genetic code and showed that RNA controlled the production of specific types of protein . </P>

Who was responsible for cracking the code of dna
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