Why does DNA synthesis only proceed in the 5' to 3' direction?
a. because DNA polymerases can only add nucleotides to the 3' end of a polynucleotide strand
b. because the 3' end of the polynucleotide molecules is more electronegative than the 5' end.
c. becuase that is the direction in which the two strands of DNA unzip
d. because that is the only direction that the polymerase can be oriented
e. because the chromosomes are always aligned in the 5' to 3' direction in the nucleus.
This solution goes through the specific properties of the enzyme DNA polymerase III within the context of cell and molecular biology.