1. DNA REPLICATION
KEY CONCEPTS:
What are the steps in DNA Replication?
Why does DNA replicate itself?
Vocabulary:
Template
DNA Polymerase
Mutation

2. DNA Replication The process of copying a DNA molecule
DNA replicates before cells divide
Why is it important for DNA to replicate before cells divide?

3. Quick Review… DNA is made up of 2 strands of nucleotides
The 2 strands are complementary
A pairs with?
C pairs with?
The strands are held together by hydrogen bonds between each of the nitrogen bases

4. Quick Review… What do the orange circles represent?
What do the blue pentagons represent?
What do A, T, G, and C represent?

5. DNA Replication
During replication each strand is used as a template to make two new DNA molecules
What does template mean? replication mean?

6. Original RIGHT with new left strand
DNA Replication
AND
Original LEFT with
new right strand
Original RIGHT with new left strand
Original DNA

7. Steps in DNA Replication
Double helix shape unwinds
An enzyme unzips the DNA molecule
Breaks the hydrogen bonds between the strands
Free nucleotides in the nucleus pair up with the nucleotides on the DNA strands forming new hydrogen bonds

8. Steps in DNA Replication
Original
DNA
DNA
unzips
Free nucleotides pair up with the original LEFT strand
Free nucleotides pair up with the original RIGHT strand

9. Steps in DNA Replication
The DNA winds back up into a double helix
What are the final products of DNA replication?

10. DNA Replication
What enzyme is used to unwind the DNA?

11. DNA Replication
Summarize the steps of DNA replication in a flow map below:

12. Why Replicate?
Every new cell needs its own copy of the genetic material
2 new identical cells
DNA copied

13. Accuracy
Replication is also very accurate – only one in a billion base pairs are incorrectly paired!
If mutations occur, DNA molecules can self-correct so the genetic code remains the same
Why is it important for DNA to replicate accurately?