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Speed of DNA Replication
The Genome of complex eukaryotes is huge and the process of DNA Replication should be incredibly fast. It is amazing that a Chromosome of 250 million pair of bases can be replicated in several hours. The speed of DNA replication for the humans is about 50 nucleotides per second per replication fork (low speed comparing to the speed of the bacterial DNA Replication).But the human Genome can be copied only in a few hours because because many replication forks take place at the some time (multiple initiation sites)

DNA Replication
One major question for the human mind is how life continues. One of the most important mechanisms for all life cells to give offsprings is undoubtedly the DNA Replication. DNA Replication answers to the question: "When a cell divides, where the extra DNA comes from?". What "DNA Replication" is? It is the process that can duplicate the DNA of a cell. The next step is the cell to duplicate!
n the eukaryotes (organisms with cell that have nucleus) the DNA is formed in two strands, each composed of units called Nucleotides. The two strands look like two chains that form the DNA Double Helix. The DNA Replication Process is capable of opening the Double Helix and separating the two strands. Then the two strands are copied. As a result two new DNA molecules are created. The next step is the cell division. After that a daughter cell is created. In its nucleus lies a copy of the parental DNA.

Follow the links in the left menu in order to find more info about the DNA Replication Process.

The Biochemical Reactions

* DNA replication begins with the "unzipping" of the parent molecule as the hydrogen bonds between the base pairs are broken.
* Once exposed, the sequence of bases on each of the separated strands serves as a template to guide the insertion of a complementary set of bases on the strand being synthesized.
* The new strands are assembled from deoxynucleoside triphosphates.
* Each incoming nucleotide is covalently linked to the "free" 3' carbon atom on the pentose (figure) as
* the second and third phosphates are removed together as a molecule of pyrophosphate (PPi).
* The nucleotides are assembled in the order that complements the order of bases on the strand serving as the template.
* Thus each C on the template guides the insertion of a G on the new strand, each G a C, and so on.
* When the process is complete, two DNA molecules have been formed identical to each other and to the parent molecule.