I am confused about how the nucleophilic attack occurs in DNA replication.I watched this video from a biology professor (https://www.youtube.com/watch?v=y4hKibS2fAo)
I watched this video which stated that during DNA replication, the hydroxl group forms a covalent bond with the phosphate and the two phosphorus groups are a leaving group.
I understand the basics of these kinds of reactions, but this one just seems confusing. I can see that the oxygen which was part of the hydroxl group forms a covalent bond with phosphorus. But what happens to the hydrogen? And why does the the double bond and position of the HO change position from the first picture to the second picture?
There are also some pictures which show water being produced. But the video states that the hydroxl group is forming a bond with the phosphate group. How does that work?
Thanks a lot