0845 numbers, for example, are free to call for up to an hour, during the inclusive minutes of your call package if you're a BT customer. Yet call an 0844 number and you'll be charged up to 5.1p/minute, plus a connection fee of up to 15p.
The resulting mRNA is a single-stranded copy of the gene, which next must be translated into a protein molecule. During translation, which is the second major step in gene expression, the mRNA is read according to the genetic code, which relates the DNA sequence to the amino acid sequence in proteins (Figure 2).
The sequence of bases on the RNA forms a code for the amino acid building blocks of the protein. The word translation seems particularly appropriate for this process since the information contained in the DNA is translated from the four-character alphabet of the bases to the twenty-character alphabet of the amino acids. The construction of the proteins is carried out on the ribosomes of the host cell.