DNA Replication

DNA replication is an important process because before a cell can reproduce, it has to replicate. An important factor that affects DNA replication is whether the cell is a prokaryote (no nucleus) or a eukaryote (yes nucleus). DNA replication takes place in the nucleus for a eukaryote and in the cytoplasm for a prokaryote. There are five basic steps to replication. The steps use five different enzymes and reads from 3 prime or 3 Carbon end (OH-) to the 5 prime or 5 Carbon end. THe beginning enzyme for the first step is called Helicase, which unwinds the double stranded DNA by breaking down the hydrogen bonds between nitrogen bases. Then RNA primase (enzyme) makes a polar end for DNA polymerase III and puts down RNA nucleotides. Then DNA polymerase III proof reads to make sure the replication has no mistakes. Then DNA polymerase I replaces RNA with DNA because DNA is too big to pass the cell membrane. Finally the enzyme Ligase attaches the Okazaki fragments (short fragments of DNA synthesized on the lagging strand) together.

Here is a link to a youtube video animation of DNA replication:
DNA replication animation on youtube
http://www.youtube.com/watch?v=teV62zrm2P0