And the reason the two DNA molecules run antiparallel is to ensure that the bonding between our nitrogenous bases is exactly right, so that we create strong bonds between our two DNA molecules and so that our double stranded DNA molecule basically doesn't unzip itself spontaneously. So this is a slightly better description of our DNA molecule because this shows our double helix structure. So we have the blue and our purple strand. So the blue one begins at the five end and goes all the way to the three N, while the pink begins at the three N and goes all the way to the five end. And this is what we mean by the antiparallel directionality, where one of our single stranded DNA runs from the five to three, while the other one runs from the three to five. Now, one other thing that we have to notice is that the sugar as well as the phosphate within our double stranded DNA points outside of that DNA while inside that double stranded DNA double helix structure, we have our nitrogenous basis.