1. Agenda
I can…
List and describe the various enzymes involved in DNA replication.
Sketch the steps and products of DNA replication.
GoFormative:
As you enter, log in to your accout and take the “Discovery & Structure of DNA quiz”
DNA Replication Notes
Gizmo OR Modeling Activity
DNA Structure & Replication Practice
Quizlet Live

2. DNA Replication The process of copying DNA.
Overall: Two nucleotide chains separate and serve as TEMPLATE for a new nucleotide chain.
Recall, when does DNA replication occur? Before what stages?

3. DNA Replication: Steps 1
1. DNA is split down the middle when helicase unzips DNA
Breaks the hydrogen bonds between base pairs
This forms a replication fork
Occurs in multiple locations on the DNA helix

4. DNA Replication: Steps 2
2. DNA polymerase builds new DNA strands by adding complementary bases to each individual strand
The nitrogen bases on each strand are used as a pattern for a new strand.
Each strand functions as a template upon which a new, missing half is built.

5. DNA Replication: Step 3
3. Each new double helix consist of one old and one new strand. Semi-conservative: One of the original strand, one new
old new new old

6. Lagging strand and okazaki fragments
Leading Strand: copied continuously in the same direction as the replication fork. Lagging Strand: created in small Okazaki fragments in the opposite direction of the replication fork.

7. Original strands of DNA
You are left with 2 exactly identical molecules of DNA
Replication assures that new cells will carry the same genetic information as each other and as the parental cell.
Semi-conservative Model
Original strands of DNA
Original
New
New
Original O N N O

8. Mutations
Despite its speed (50–500 pairs per second), replication is very accurate. It makes approximately one mistake in every billion nucleotide pairs. Mistakes in the DNA sequences are called mutations. DNA polymerases proofreads the new daughter strands and fixes these mistakes.

9. Agenda
I can…
List and describe the various enzymes involved in DNA replication.
Sketch the steps and products of DNA replication.
GoFormative:
As you enter, log in to your accout and take the “Discovery & Structure of DNA quiz”
DNA Replication Notes
Gizmo OR Modeling Activity
DNA Structure & Replication Practice
Quizlet Live

10. Gizmo or modeling
If you and your partner choose the Gizmo, grab one of your computers and log on to explorelearning.com. I will come around with a log in for you.
If you and your partner choose the modeling activity, go to the left wall and pick up 28 black pentagons, 28 white tubes, 14 white rods, and 28 tubes of the following colors, any combination works: blue, green or orange. You will also need pen and paper to write on.
Once you finish your activity, come to the front and pick up a DNA structure and replication practice worksheet.
If you should finish all of this, continue working on your Keystone Review Packet