1. KEY CONCEPT DNA replication produces copies the genetic information of a cell.

2. Replication copies the genetic information.
The rules of base pairing direct replication.
DNA is replicated during the S (synthesis) stage of the cell cycle.
Each body cell gets a complete set of identical DNA.

3. In your packet

4. Proteins carry out the process of replication.
Identify the Structures:
Original DNA serves as template for assembling new.
Free-floating nucleotides form hydrogen bonds with the template strand.
Enzymes and other proteins do the actual work of replication.
DNA Helicase Enzymes unzip the double helix.
DNA Polymerase Enzymes pull in nucleotides and bond the sugar/phosphate backbone.
nucleotide
The DNA molecule unzips in both directions.

5. Bonds! DNA polymerase enzyme helps hydrogen-bond the nucleotides.
Polymerase forms covalent bonds between backbone sugars & phosphates in the new strand.
DNA polymerase
new strand
nucleotide

7. Replication is fast and accurate.
DNA replication starts at many points in eukaryotic chromosomes.
There are many origins of replication in eukaryotic chromosomes.
DNA polymerases can find and correct errors.

8. DNA replication is a semi-conservative process.
1. Replication forks are formed in many places along eukaryotic DNA. This speeds up the process. Enzyme DNA Helicase opens the hydrogen bonds in both directions.
2. Enzyme DNA Polymerase pulls in free nucleotides to assemble the new strand.
3. Polymerases travel in opposite directions, bonding the nucleotides and backbones of the new strands.

9. DNA replication is semiconservative: One old, one new...
4. Two new molecules of DNA are formed, each with an original strand and a newly formed strand.
DNA replication is semiconservative: One old, one new...
original strand
new strand
Two molecules of DNA

10. Replication copies the genetic information.
Replication assures that every cell has a complete set of identical genetic information. Recall that your human eukaryotic DNA is divided into 46 chromosomes that are replicated during the Synthesis phase of the cell cycle. So your DNA is copied once per cell cycle, and each cell in your body has a complete set of DNA.

11. Complete as HW