The "central dogma" of
genetics states that each sequence of nucleotides on a segment of DNA that
codes for the production of a protein is called a gene.
Ribosomes cannot construct polypeptides from the genetic code carried by
DNA but can do so from RNA. Information flows from the DNA to messenger
RNA (mRNA) to amino acid sequence of the growing polypeptide. The
process of building a molecule of mRNA is called transcription,
while the building of a new protein from the mRNA code is called translation.