Question

what was marshall nirenberg and heinrich matthaeis contribution to our current understanding of the genetic code?
discovery of codons
discovery and extraction of dna
creation of a model of dna
creation of photo 51

Explanation:

Marshall Nirenberg and Heinrich Matthaei conducted experiments in 1961 that led to the discovery of codons, the three - nucleotide sequences in mRNA that specify amino acids. The discovery of DNA and its extraction was done by others. Watson and Crick created a model of DNA. Photo 51 was created by Rosalind Franklin.

Answer:

discovery of codons