And notice that for the case of the parent strand that runs from the three to the five direction, the DNA polymerase basically creates the nucleotides begin with the five and ending with the three end. So we see that DNA polymerase has no problem synthesizing our daughter's strand on the parent molecule that runs three to five. However, what happens in this case for the parent strand that begins with the five and ends with the three? If our DNA polymerase attaches to this side it must synthesize in the three to five direction and that is not allowed. Remember, the DNA polymerase can only synthesize in the five to three direction, it cannot synthesize from the three to five direction. So we see that this strand that is formed by using the three to five parent strand is known as the leading strand.